| Extension | Information |
| I | C++ Preprocessor Intermediate File (Borland Software Corporation) |
| I | INTERCAL File |
| I | Phase Vocorder Analysis Data |
| I | Progress Database Include File (Progress Software) |
| I | Integra Database (Imagina Software) |
| I | APLAC Source Code Data File (APLAC) |
| I-E | i-Enforce Security File (ICM Conversions & Management) |
| I0 | Winter Windows Scheduler File |
| I00 | (100-103) Winphone Phonebook |
| I16 | Nokia Phone Logo File (Nokia) |
| I17 | Pixel Power Collage |
| I18 | Pixel Power Collage |
| I1C | IBM Voice Type Language Newuser File |
| I1I | IBM Voice Type Language Newuser File |
| I2C | IBM Voice Type Language Newuser File |
| I2I | IBM Voice Type Language Newuser File |
| I2S | Invision for mIRC Settings |
| I3 | Modula-3 Interface Source |
| I3C | IBM Voice Type Language Newuser File |
| I3I | IBM Voice Type Language Newuser File |
| I3ML | I3ML Source Page |
| I66 | Interactive66 Graphic Design Information |
| IA | Roland Garros Tennis Person File |
| IA6 | IApproach Data File (Workfile) (Tdata, Inc.) |
| IAF | Outlook 97 and 2000 E-mail Account Settings (Microsoft) |
| IAF | Outlook Express Account Settings (Microsoft) |
| IAF | IAFA Document |
| IAF | Quikscribe Intelligent Audio File (Quikscribe Pty Ltd) |
| IAFA | IAFA Document |
| IAM | Inventor CAD (Autodesk, Inc.) |
| IAN | Sterling Software COOL Business Team Model File |
| IAP | ASM Palette |
| IAP | TeamBG File |
| IAP | Iguana Active Server Active Page Script (ILan Game) |
| IAR | CD Katalog (KRISoftware) |
| IAS | Iguana Active Server Script (ILan Game) |
| IAX | IBM Image Access Executive Bitmap |
| IB7 | Pixel Power Collage |
| IBA | IBasic Source Code File |
| IBA | Image |
| IBA | InfoHandler Infobase File (MDE Software) |
| IBC | IncrediBar Cursor File (IncrediMail Ltd.) |
| IBD | PDS Picture |
| IBD | Windows Installer File (Microsoft) |
| IBF | Instant Backup |
| IBG | Bert's Dinosaurs File |
| IBG | NASA PDS Graphic Format |
| IBK | National Construction Estimator 32 Picture File |
| IBK | Sound Blaster Instrument Bank |
| IBK | (Kodak) Imaging for Windows Bookmark (Microsoft Corporation) |
| IBL | IBasic Component Language File |
| IBL | PCLTool Index-by-Location File (Page Technology Marketing, Inc.) |
| IBM | Archdos Compressed File |
| IBM | Commodore Amiga Graphics |
| IBP | IsoBuster CD/DVD Layout File (Smart Projects) |
| IBQ | IsoBuster Optical Media Data Container File (Smart Projects) |
| IBS | i2 iBase File |
| IBS | IncrediBar Skin (IncrediMail Ltd.) |
| IBT | IBTracer Infiniband Link And Protocol Analyzer InfiniBand Trace File (Computer Access Technology Corporation) |
| IBX | Interscope BlackBox File |
| IBY | ROM Image Component Include File |
| IC | Modula-3 M3CG Intermediate Language File |
| IC | Spice Initial Condition |
| IC1 | Imagic Bitmap Graphic |
| IC1 | ZyIMAGE Index |
| IC2 | IMagic Bitmap Graphic |
| IC3 | IMagic Bitmap Graphic |
| ICA | Citrix Independent Computer Architecture File (Citrix) |
| ICA | Image Object Content Architecture (IOCA) Graphics File |
| ICAL | iCal Personal Calendar (Apple Computer, Inc.) |
| ICB | Image Capture Board |
| ICB | Targa Bitmap |
| ICC | Animation Softdisk |
| ICC | Apple ColorSync 2.0 (Apple Computer, Inc.) |
| ICC | ICC Profile Format File |
| ICC | IronCAD Catalog |
| ICC | Kodak Printer Image |
| ICD | ASTi Model Builder |
| ICD | File Associated with Many Games |
| ICD | IronCAD 2D CAD File |
| ICD | Rate Structure File |
| ICD | Rayman2 Game File |
| ICE | Archive |
| ICE | Cooltalk Audio |
| ICE | Freeze! Compressed Archive (Reeve Soft) |
| ICE | ICEOWS Compressed File (Rapha?l et Batrice Mounier) |
| ICF | Cheyenne AntiVirus |
| ICF | ICOM CS-2100 Radio Programming Data |
| ICF | INI Creator for X10 Remote Control |
| ICF | Insane Chat Saved Conversation |
| ICF | RapidForm2000 (INUS Compression Format File (INUS Technology, Inc.) |
| ICL | Clean File |
| ICL | Icon Library File |
| ICM | Earl F. Glynn Color Tablecolor Table |
| ICM | ICC Profile, Acer Monitor Drive |
| ICM | Image Color Matching Profile File (Kodak) |
| ICM | Windows Color Matching Control (Microsoft Corporation) |
| ICMP | Internet Control Message Protocol |
| ICMS | Ragtime Extensions File |
| ICN | AT&T Graphic Format |
| ICN | Bert's Dinosaurs File |
| ICN | Icon Programming Language Source Code File |
| ICN | Micrografx Icon |
| ICN | RIPTerm Image |
| ICN | SunOS Mono Icon |
| ICN | HP Palmtop 100/200LX Icon |
| ICO | GIMP Icon (The GIMP Team) |
| ICO | Windows Icon (Microsoft) |
| ICO | Sun Icon/Cursor |
| ICO | OS/2 Icon |
| ICON | Sun Icon/Cursor |
| ICP | InterCept File |
| ICP | UNIX Icontact Parameter File |
| ICQ | ICQ Saved File (ICQ Inc.) |
| ICR | NCSA Telnet Interactive Color Raster Graphic |
| ICS | Image Cytometry |
| ICS | Inovate 3D CAD File |
| ICS | IronCAD 3D CAD File |
| ICS | Outlook Calendar File (Microsoft) |
| ICS | SwiftView ICS Command File (SwiftView, Inc.) |
| ICS | iCalendar Calendar Data |
| ICT | TIFF and ISO Image Related File |
| ICV | Bond .AVI Film |
| ICV | In Chair Viewing |
| ICW | Icon |
| ICW | InterCAD File |
| ICW | MS Internet Explorer Internet Connect Wizard |
| ICX | More Than Words File |
| ICX | VisualAge Smalltalk Enterprise Program Image File (IBM) |
| IC_ | Compressed LCT File |
| ID | 3D Graphic |
| ID | Disk Identification File |
| ID | Gamecode |
| ID | AOL Instant Messenger Buddy Icon (America Online, Inc.) |
| ID | Notes ID File (IBM) |
| ID | MS Data Map (Microsoft) |
| ID | Pegasus Mail (David Harris) |
| ID3 | ID3 Resource |
| IDA | IIS Server File (Microsoft) |
| IDAPI | Integrated Database Application Programming Interface (Borland Software Corporation) |
| IDB | A-B-CD Info File |
| IDB | Database Used by Disassembler |
| IDB | Delphi Pascal Object File |
| IDB | Developer Intermediate File (Microsoft) |
| IDB | IDA Database |
| IDB | MS Developer Intermediate MDPX File |
| IDC | Core IDC |
| IDC | IDA C Language Source Code |
| IDC | Internet Database Connector Document |
| IDC | Structured Query Language (SQL) |
| IDD | MIDI Instrument Definition |
| IDD | Complete Works Database-related File (Toplevel Computing) |
| IDE | C++ Project (Borland Software Corporation) |
| IDE | Grand Theft Auto III Model IDs and Properties (Take-Two Interactive Software, Inc.) |
| IDE | Integrated Development Environment Configuration File |
| IDE | Sophos Anti-Virus Virus Identity File |
| IDE | ideCAD Architectural Architectural 3D Design Model (ideYAPI Ltd. Sti.) |
| IDE | ideCAD Structural Structural 3D Design Model (ideYAPI Ltd. Sti.) |
| IDEA | Brainbloom Document (Gael Limited) |
| IDEMO | Instant Demo Project File (NetPlay Software) |
| IDENTIFIER | Internet Explorer Zone Identification Information (Microsoft Corporation) |
| IDF | ARTiSAN Real-time Studio ID |
| IDF | Identification File |
| IDF | MIDI Instruments Definition File (Microsoft) |
| IDF | Printed Circuit Board Data Exchange File |
| IDI | i-deas Web ACCESS File |
| IDIF | Netscape Saved Address Book |
| IDL | CRiSP Harvest File |
| IDL | OMG CORBA Interface Definition Language |
| IDL | Snappy Devdocs |
| IDL | Visual C++ Interface Definition File (Microsoft) |
| IDLK | InDesign Lock File (Adobe Systems Inc.) |
| IDM | Ulead Photo Express Messages File |
| IDMEF | Snort File |
| IDQ | Internet Data Query File |
| IDQ | Structured Query Language (SQL) Query |
| IDR | CompactDRAW Object(s) (MediaChance) |
| IDS | Minos 3D Data File |
| IDS | IDA Imported Names Format |
| IDS | Infini-D Scene File |
| IDS | Infinity Game Engine Numbers to Description Map (BioWare Corp.) |
| IDS | WFO-A Data |
| IDT | Identification |
| IDT | Output of DLL2IDT Utility |
| IDT | Text Archive Table |
| IDT | Windows Installer File (Microsoft) |
| IDU | Interleaf Desktop Utility (BroadVision) |
| IDV | Inventor Design View Tree (Autodesk, Inc.) |
| IDW | IntelliDraw Vector Graphic (Adobe) |
| IDW | Inventor CAD (Autodesk, Inc.) |
| IDX | ArcView Geocoding Index For Read-Only Datasets (ESRI) |
| IDX | Clip Gallery 1.x Index (Microsoft) |
| IDX | Corel QuickFinder Information |
| IDX | FAX File |
| IDX | FoxPro Index (Microsoft) |
| IDX | ICQ Index (ICQ Inc.) |
| IDX | Index |
| IDX | Pro/ENGINEER Index File (PTC) |
| IDX | LaTeX Index |
| IDX | Outlook Express Mailbox Index (Microsoft) |
| IDX | Stork Format Header Information |
| IDX | Symantec Q&A Relational Database Index File |
| IDX | AOL Temporary Internet Mail File |
| IDX | Complete Works Index File (Toplevel Computing) |
| IDX | NoX |
| IDX | Java Applet Cache Index (Sun Microsystems, Inc.) |
| IDX | Ca Visual Objects Platform for Developer (CAVO) Index File (CA) |
| IDY | Debug Information File |
| IDY | Index File |
| IDZ | i-deas Web ACCESS File |
| ID_ | C Poet Compressed Disk1 File |
| IE1-3 | Internet Explorer 3 Address Book |
| IE3 | Internet Explorer 3 File |
| IEE-695 | IEEE 695 Information (Hewlett Packard) |
| IEF | Image File |
| IEL | Erazer98 File |
| IEM | Informix Error Message |
| IES | Photometric File Data |
| IF9 | Pixel Power Collage |
| IFB | Siebel Interface Configuration File (Siebel Systems) |
| IFC | All Image Compressed Image File (Rundegren.com) |
| IFD | Jet Form Design Form |
| IFF | Amiga Bitmap Graphic (Amiga) |
| IFF | Amiga Sound (Amiga) |
| IFF | Bitmap Graphic |
| IFF | DESR VFF Greyscale Bitmap Image |
| IFF | Graphic, Sound |
| IFF | Deluxe Paint Image (Electronic Arts, Inc.) |
| IFF | Philips CDI File |
| IFF | ProWrite Document |
| IFF | Simple Musical Score |
| IFF | Sun TAAC Image File |
| IFF | TDI Explore & Alias Wavefront Image |
| IFF | TextCraft Document |
| IFF | The Sims Object/Data File (Electronic Arts (Maxis)) |
| IFILE | Amaya i386 File |
| IFL | Descent 3 Ship Graphic |
| IFM | Brighterion iPrevent Fraud Model |
| IFM | Shana Informed Filler |
| IFM | IFS Applications Message File (IFS AB) |
| IFN | Amma Lsb v1.0 Initialization |
| IFO | DVD Info File |
| IFO | ImageForge Pro Graphic Object Layer Data |
| IFO | Info File |
| IFP | KnowledgeMan Script |
| IFR | Formula 1 Racing Databin Cars Common File |
| IFS | Fractint Iterated Function System Fractal |
| IFS | IconForge Image EXE Library |
| IFS | OS/2 Warp Installable File System |
| IFS | Yuvpak Compressed Fractal Image |
| IFS | Fractint Iterated Function System Parameters |
| IFS | InfoSlips Secure Information Package (InfoSlips) |
| IFU | All Image Uncompressed Image File (Rundegren.com) |
| IFX | ImageSoft v2.00 Graphic |
| IFX | IMAGINE Effect File |
| IFX | Rational XDE (IBM) |
| IFX | Fax File |
| IG | Modula-3 Generic Interface Source |
| IGC | Global Positioning System Datalog File (Fdration Aronautique Internationale) |
| IGC | SeeYou Flight Data (Naviter) |
| IGES | IGES-Format |
| IGES | Initial 2D/3D Graphics Exchange Specification |
| IGF | Hijack Graphic Bitmap |
| IGF | Image Systems |
| IGF | Inset Systems Metafile |
| IGF | Sound file |
| IGF | Vector Graphic |
| IGL | inSORS IGLayout Layout File |
| IGL | IGOR Saved Level File (Elmer Productions) |
| IGM | inSORS IGClient Meeting File |
| IGN | ICQ Igonre List (ICQ Inc.) |
| IGNORE | Likely a Text File Some programs write out a temporary file with an extension like .IGNORE. These are often text files. Just because it says you can ignore it does not mean you should delete it. |
| IGP | InfoGest Configuration/Profile Settings (S.C. NVN Group S.R.L.) |
| IGP | Igor Reader Sheet Music File |
| IGP | IGOR Player File (Elmer Productions) |
| IGR | Intergraph SmartSketch Drawing |
| IGR | SmartSketch Drawing Design |
| IGS | CAD Overlay |
| IGS | IGES-Format |
| IGS | Image Systems Grayscale, 8-bits |
| IGV | inSORS IGClient Venue File |
| IGX | Process (iGrafx (a division of Corel Inc.)) |
| IHP | Watcom Help File |
| IHS | Bink Inbound History |
| IHT | Intranet Connector Script File (SCORT) |
| IHTML | Inline HyperText Markup Language (Inline Internet Systems, Inc.) |
| II | Gcc Preprocessed C++ Source Code |
| IID | Tonline BSW4 Fnstall Lid File |
| IIF | QuickBooks Import/Export Interchange File (Intuit, Inc.) |
| III | Intel IPhone Compatible File (Intel) |
| III | ARC+ Drawing (ACA) |
| IIL | Norton CleanSweep Installation Log (Symantec) |
| IIM | Inshape Graphic |
| IIM | Interscope InstallMaster Setup Project |
| IIM | iOpus Internet Macro |
| IIM | Music Module |
| IIMG | Interleaf Graphic |
| IIT | Install Maker Install Info File (Clickteam) |
| IIX | Rational XDE (IBM) |
| IJS | J Interpretor Script File |
| IJX | J Language Execution Window (Source Code) (Jsoftware) |
| IKL | InkBall (Microsoft) |
| IKO | Windows Icon Resource |
| IL | FORTRAN 90 Inline Expansion File |
| IL | Icon Library |
| IL | MSIL Assembler Input File (Microsoft) |
| IL | Euphoria Shrouded Source Code (Rapid Deployment Software) |
| ILB | Scream Tracker Data |
| ILBM | Deluxe Paint Graphic (Electronic Arts, Inc.) |
| ILBM | Amiga Interleaved Bitmap Format (Amiga) |
| ILBM | Graphic, Sound |
| ILF | Omniscope Application-Specific Data (Iokio Ltd) |
| ILF | SMS Insight Log File (Ag Leader Technology, Inc.) |
| ILG | TeX MakeIndex Track File |
| ILG | InstallShield Log File (InstallShield Software Corporation) |
| ILK | Ilink Program Format Outline (Microsoft) |
| ILL | 2D Graphic |
| ILL | Agati Illustrated Image |
| ILL | ILL Transaction File |
| ILL | Illustrator Prologue (Adobe) |
| ILM | Amiga IFF Image (Amiga) |
| ILM | CAS 200 QDA v3.0 Image List Mode File |
| ILM | Illuminatus Opus Multimedia File |
| ILM | Iomega Zip Drive Speed Configuration File |
| ILM | Satsang Quiz File |
| ILPLOPTIONS | InterLock and PowerLock |
| ILPLVOUCHERS | InterLock and PowerLock |
| ILS | Internet Security And Acceleration Server Summary (Microsoft) |
| ILS | Win3 Windows Word File |
| ILSR | Iomega Reader |
| ILV | ILOG View File |
| ILVG | iLiving P-to-P |
| IM | 3D Graphic |
| IM | Sun Raster File |
| IM | AOL Instant Messenger Grey Scale Image (America Online, Inc.) |
| IM04 | Image Sun Raster |
| IM1 | Sun Raster File |
| IM24 | Bitmap Graphic |
| IM30 | Image Sun Raster |
| IM32 | Bitmap Graphic |
| IM5 | Visilog |
| IM5 | Visilog (NorPix, Inc.) |
| IM7 | DaVis Graphic (LaVision GmbH) |
| IM8 | Sun Raster Graphic |
| IM? | 2D Graphic |
| IMA | AOL Instant Messenger Grey Scale Image (America Online, Inc.) |
| IMA | EGO - Chart - Autumn Mirage Vector Graphic |
| IMA | Mirage Vector Graphics |
| IMA | ImageMixer (Pixela Corporation) |
| IMA | WinImage File |
| IMA | Zenographics image |
| IMA | IncrediMail Animation (IncrediMail Ltd.) |
| IMAGE | Disk Copy, ShrinkWrap Disk Image |
| IMAGE | Squeak Code File |
| IMAGINE | Object & Texture Imagine 3.0 |
| IMAKE | Imake File |
| IMB | IncrediMail (IncrediMail) |
| IMC | IncrediMail (IncrediMail) |
| IMC | MontagePlus Thumbnail Image Collection (Serif Europe Ltd.) |
| IMD | Caseware IDEA |
| IME | IncrediMail Emoticons (IncrediMail Ltd.) |
| IME | Global Input Method Editor (Microsoft) |
| IMESHDEF | iMesh Skin (iMesh) |
| IMF | ImageForge/ImageForge Image EXE Library Saved Filtered Brush |
| IMF | IncrediMail Letter/eCard (IncrediMail Ltd.) |
| IMF | MIDI Music File |
| IMG | Grand Theft Auto III .DFF and .TXD Archive (Take-Two Interactive Software, Inc.) |
| IMG | Idrisi32 Raster Image |
| IMG | Image Whatnot / Erdas Imagine MIS / Radiance / Starbase |
| IMG | Microtek Eyestar |
| IMG | Planetary Data System |
| IMG | Radiance Scene Description Image |
| IMG | Sharp GPB |
| IMG | Starbase |
| IMG | Ventura Publisher/GEM VDI Image Format Bitmap |
| IMG | Vicar |
| IMG | Vivid Ray-tracer |
| IMG | ADEX Corporation ChromaGraph Graphics Card Bitmap Graphic |
| IMG | Alias Bitmap Graphic |
| IMG | Apple Macintosh Disk Copy Format (Apple Computer, Inc.) |
| IMG | AutoCAD CAD-Camera (Autodesk, Inc.) |
| IMG | Bitmap Graphic |
| IMG | CloneCD Image (SlySoft Inc.) |
| IMG | Disk Copy, ShrinkWrap Disk Image |
| IMG | ERDAS IMAGINE Image Format (Leica Geosystems , LLC) |
| IMG | Floppy Image File |
| IMG | Grand Theft Auto III File (Take-Two Interactive Software, Inc.) |
| IMG | Img Software Set Bitmap |
| IMG | QEMU Qcow Disk Image (Fabrice Bellard) |
| IMG | All Image Raw Image (Rundegren.com) |
| IMH | IncrediMail Data File (IncrediMail Ltd.) |
| IMI | IncrediMail Animation (IncrediMail Ltd.) |
| IMI | Turbo Pascal DOS File (Borland Software Corporation) |
| IMJ | JFIF File With a Microsoft Windows BMP Header |
| IMJ | Pegasus Image Corp Bitmap |
| IMK | IncrediMail License License (IncrediMail Ltd.) |
| IML | ACT! Internet Mail Message File (Best Software CRM Division) |
| IMM | IncrediMail Trash (IncrediMail Ltd.) |
| IMN | IncrediMail Notifier (IncrediMail Ltd.) |
| IMP | Babya Installer Archive |
| IMP | Crayola Art Image |
| IMP | DVD File |
| IMP | FileMaker Database Translation Filter |
| IMP | IMP Archive |
| IMP | Improv Spreadsheet (IBM) |
| IMP | Pascal Implementation |
| IMP | Urban Chaos Game File |
| IMP | WinIMP Archive (Technelysium Pty Ltd) |
| IMP | TEX-DESIGN Clothing Design File (Koppermann Computersysteme GmbH) |
| IMP | Gemstar eBook Publisher eBook (Gemstar eBook) |
| IMQ | ImageQ Presentation |
| IMQ | NASA Planetary Image |
| IMR | Cognos Impromptu Report Writer |
| IMS | IconForge |
| IMS | Incredimail Graphic Skin (IncrediMail Ltd.) |
| IMS | Music File |
| IMS | Rebel Assault File |
| IMSP | Survey Pro Survey File (iMagic Software) |
| IMT | IMNET Image |
| IMT | egseing Image Mode |
| IMV | Yahoo Instant Messenger IMVironment |
| IMV | ImageMixerVCD Project File (Pixela Corporation) |
| IMW | Imageware Surfacer 3D CAD Surface Geometry |
| IMW | IncrediMail Sound (IncrediMail Ltd.) |
| IMX | SAS/IML Workshop Matrix (SAS Institute Inc.) |
| IMX | DaVis Binary Image File (LaVision GmbH) |
| IMY | iMelody Ringtone Format (Infrared Data Association) |
| IMZ | Compressed Floppy Image |
| IMZ | WinImage File |
| IM_ | Improve Compressed Audio File |
| IN | Input File |
| IN | McAfee Antivirus |
| IN$ | HP NewWave Install File |
| IN0 | INI Backup |
| IN1 | INI Backup |
| IN3 | Harvard Graphics Input Device Driver (Harvard Graphics) |
| IN7 | Ox Object-Oriented Matrix Programming Language PcGive 7 Data File |
| INA | DOS File |
| INB | Rebel Assault Backup |
| INB | Vermont HighTest Script |
| INB | Visual Expert Source Code Documentation |
| INC | Active Server Include File |
| INC | Assembler language or Active Server Include File |
| INC | Astro Windows |
| INC | Include File |
| INC | Internet Connection File |
| INC | JAWS for Windows Text File (Freedom Scientific) |
| INC | MS-Backup Incremental File |
| INC | PovRay 2 or 3 |
| INC | Spice Include File Subcircuit |
| INC | Wincommander Include File |
| INCD | InCopy/InDesign Link File (Adobe) |
| IND | dBASE IV |
| IND | LaTeX or TeX Makeindx Index |
| IND | Well of Souls Game File |
| IND | Windows Shared Database File |
| IND | Windows/Applog Index |
| IND | Foxmail E-Mail Box Index |
| IND | InDesign Publication (Adobe Systems Inc.) |
| IND | Notes List files for Compact Task on Domino Server (IBM) |
| IND | XMap Dataset Index (Delorme) |
| INDD | InDesign Document (Adobe Systems Inc.) |
| INDEX | Index File |
| INDIGO | Indigo Graphics Format [Eddi Litvak] |
| INF | Autorun |
| INF | BLUEWAVE Information File |
| INF | Information or Setup File |
| INF | OS/2 2.0 Information Presentation Facility (IPF) Data Format OS/2 PTR file : Cursor image file |
| INF | OS/2 Buch Hypertext Help System File |
| INF | Type 1 LaserJet Font Information File |
| INF | Type Manager Font Information (Adobe) |
| INF | Pro/ENGINEER Temporary File (PTC) |
| INFINI-D | Infini-D 3.0 Format |
| INFO | Amiga Icon (Amiga) |
| INFO | UNIX GNU Info Reader |
| INFO | ZoomBrowser Image Index (Canon, Inc.) |
| ING | MasterCook Ingredients |
| INGR | Intergraph Raster File Format |
| INH | Visual Basic Basfwin File |
| INI | Gravis UltraSound Bank Setup File |
| INI | Initialization/Configuration File |
| INI | MWave DSP Synth's GM-setup File: MWSYNTH.INI |
| INI | Simple Exchange Rate Information File Format (SERIFF) |
| INK | Mimio Ink File |
| INK | Pantone Reference File |
| INK | Tablet PC Digital Ink File (Microsoft Corporation) |
| INL | Visual C++ Inline Function File (Microsoft) |
| INM | Fax Master File |
| INN | COBOL/2 Overlay (Micro Focus) |
| INN | PHANTASMAGORIA INI File |
| INO | Inno Setup Script Files File |
| INO | Inor IPRO Software File |
| INP | CHARMM Input File |
| INP | FRANC2D Mesh File |
| INP | GIS Software Text Input File |
| INP | InPage |
| INP | Oracle Source Code |
| INP | Self-Extracting Archive Utility Project |
| INP | Tramo-Seats Input Specification File (Bank of Spain) |
| INP | ABAQUS Input File (ABAQUS, Inc.) |
| INRS | INRS-Telecommunications Sound |
| INS | 1st Reader Install Script |
| INS | AdLib Instrument Music File |
| INS | Ensoniq EPS Family Instrument |
| INS | IIS Internet Communications Settings (Microsoft) |
| INS | Inspiration Mind Mapping Software File |
| INS | InstallShield Script (InstallShield Software Corporation) |
| INS | Sample Cell / II Instrument |
| INS | WordPerfect (Corel Corporation) |
| INS | REAKTOR Instrument (Native Instruments) |
| INS | PUT Compressed File Archive (MicroFox Company) |
| INSCRIBE | InScribe 2004 Egyptian Hieroglyphs Document (Saqqara Technology Ltd.) |
| INST | 3D Graphic |
| INST | Object Oriented Graphics Library (OOGL) |
| INSTALL | Likely a Text File |
| INT | Delphi Interface Unit (Borland Software Corporation) |
| INT | Foxpro Code Page (Microsoft) |
| INT | Intermediate Code Used for Syntax Checking |
| INT | Signature Semi-compiled Program |
| INT | Unreal Tournament Mutator |
| INTER | Interspector Project File |
| INTERLOCKFAVOURITES | InterLock and PowerLock |
| INTERNETMAILSEND | Internet Mail Send Powertoy File |
| INTO | Interspector Object File |
| INU | INSPEC Configuration File |
| INV | Rainbow Six: Rogue Spear Inventory File (Red Storm Entertainment, Inc.) |
| INV | Windows Update file |
| INV | Lineage Inventory File (NCsoft Corporation) |
| INV | dnaLIMS Invoice File (dnaTools) |
| INV | Medlin Accounting Current Year Checks and Invoices (Medlin Accounting) |
| INVENTOR | Open Inventor File Translator How To [SGI] |
| INV_LOWRES | Rainbow Six: Rogue Spear Inventory File (Red Storm Entertainment, Inc.) |
| INX | ACL for Windows Index |
| INX | Foxpro Foxbase Index |
| INX | InstallShield Compiled Rules File (InstallShield Software Corporation) |
| INX | Rational XDE (IBM) |
| IN_ | Setup Information (Microsoft) |
| IN~ | King's Quest 7, Grabriel Knight, Compressed File |
| IO | Compressed Archive |
| IO | Modula-3 Object File |
| IO | IO Language Script (Steve Dekorte) |
| IOB | 3D Object TDDDB Format |
| IOB | Imagine File |
| IOB | Imagine Ver. 1 or 2 TDDDB Format |
| IOB | iOnly ME Website Generator Backup (iOnly) |
| IOB | TDDD Format 3D Graphic Database |
| IOB | Turbo Silver TDDDB Format |
| IOC | Instant ORGcharting! Organization Chart |
| IOC | Winamp Io Plug-in (File: IMGORG.IOC) (Nullsoft) |
| IOCA | Image Object Content Architecture (IOCA) Graphics File |
| IOD | DVGate DVMotion In/Out List |
| IOF | Findit Document (Microsoft) |
| IOF | Findit Document |
| IOK | Omniscope Data File (Iokio Ltd) |
| ION | 4DOS File Description |
| ION | Mascot Data |
| ION | Text Program/Installation Description |
| IOP | iOnly ME Website Generator File (iOnly) |
| IP | IconPackager File |
| IP | Interactive Physics Data |
| IP | Internet Protocol |
| IP | NRC Inspection Manual Inspection Procedures |
| IP | Profile |
| IPC | Interactive Publisher Pro Church Edition Project Data (Interactive Software Designs) |
| IPD | InstallPROG 6 EDBS Install Database |
| IPD | BlackBerry Backup File (Research In Motion Limited) |
| IPE | ItsPersonal File |
| IPE | Wacom Pen SYSTEM.INI and WIN.INI Backup |
| IPF | Grand Theft Auto III Animation Data (Take-Two Interactive Software, Inc.) |
| IPF | SMS Installer Script (Microsoft) |
| IPF | Interchangeable Preservation Format (Classic Amiga Preservation Society) |
| IPG | Mindjongg Format |
| IPH | InterPaint Hires Image |
| IPJ | Inventor Project (Autodesk, Inc.) |
| IPJ | InfinityQS SPC Project File (InfinityQS International) |
| IPK | NRG iPack File |
| IPK | Sharp Zaurus PDA Application Install File |
| IPK | internet PacKage Archive (direct Netware Group) |
| IPL | Corel Pantone Spot Reference Palette |
| IPL | Grand Theft Auto III Object Placement Data (Take-Two Interactive Software, Inc.) |
| IPL | Ink Palette |
| IPL | InstallPROG 6 EDBS File Library |
| IPL | IPLab 3.1 |
| IPL | PLATO Web Learning Network (PWLN) Temporary File (PLATO Learning, Inc.) |
| IPL22 | PLATO Web Learning Network (PWLN) Temporary File (PLATO Learning, Inc.) |
| IPLI | IPLab Graphic |
| IPM | Image Pro Plus Ver. 5 Macro (Media Cybernetics Inc.) |
| IPN | Inventor Presentation (Autodesk, Inc.) |
| IPP | Help & Manual Proprietary Image |
| IPR | IntelliJ Project XML File |
| IPR | SMART Ideas Document (SMART Technologies Inc.) |
| IPS | Game Patch File |
| IPS | International Patching System Binary Patch File |
| IPS | IPScript File |
| IPS | MENSI 3Dipsos (MENSI Corporation) |
| IPT | InterPaint Multicolor Image |
| IPT | Inventor CAD (Autodesk, Inc.) |
| IPTC | Newswire Profile |
| IPTHEME | IconPackager Icon Theme Package (Stardock Corporation, Inc.) |
| IPU | Vocaltech Iphone Internet Phone User File |
| IPW | UniPlot Graph |
| IPX | Interactive Pictures Corporation AV File |
| IPX | Ipix Spherical Panorama |
| IPX | Viewpoint iPix File |
| IPZ | ICQ Skin (ICQ Inc.) |
| IQ | IBM Query File |
| IQA | AmeriCalc Application |
| IQB | AmeriCalc Backup |
| IQC | AmeriCalc Client File |
| IQC | CADIQ Comparison Analysis Result File (ITI TranscenData) |
| IQD | AmeriCalc Database |
| IQD | Webstir File |
| IQF | Integra 3.0 Query File |
| IQI | IBM Query |
| IQJ | CADIQ Specific Tasks/Analysis Details (ITI TranscenData) |
| IQL | CADIQ Log File (ITI TranscenData) |
| IQR | IBM Query |
| IQR | CADIQ View Analysis Results (ITI TranscenData) |
| IQS | AmeriCalc Security File |
| IQS | CADIQ Summary Log File (ITI TranscenData) |
| IQT | IBM Query |
| IQU | AmeriCalc Update |
| IQY | Excel Web Query (Microsoft) |
| IQY | Internet Inquiry File (Microsoft Corporation) |
| IRC | IRCAM Format Sound |
| IRC | Nevo Infra-red Device Code (Universal Electronics Inc.) |
| IRCD | iArcade Game Package (Brooklyn Games, Inc.) |
| IRD | IRD Append File |
| IRD | Money Temporary File (Microsoft) |
| IRF | Phonecat2 Ocp97 File |
| IRF | RoomBox 6 IR Code File (Living Control) |
| IRI | Thermography Studio Infrared Image (GORATEC Technology GmbH & Co. KG) |
| IRIS | Silicon Graphics RGB |
| IRIX | Irix Make File |
| IRIX6 | Irix 6 File |
| IRIX64BIT | Irix 64 Bit Make File |
| IRK | iArcade Game Package (Brooklyn Games, Inc.) |
| IRL | ILOG JRules ILOG Rule Language File (ILOG, Inc.) |
| IRS | WordPerfect Resource File (Corel Corporation) |
| IRTP | Graphicon-2000 Interactive Real-Time PHIGS Graphic |
| IRV | XMap Workfile (ImageReg) (Delorme) |
| IRX | Brewer Lamp Irradiation File |
| IRX | IBM Mainframe Rule File |
| IRX | PS2 Modified Elf Object File |
| IRZ | iROS Application Packaging Unit (Interactive Workspaces Project, Stanford University) |
| IS | Modula-3 Intermediate Assembly File |
| ISBN | HM3 Tutorial Software |
| ISC | RVS-COM Prepaid SMS Package File (Living Byte Software GmbH) |
| ISC | GRDSOZ4W ISCII File |
| ISC | Xilinx Integrated Software Environment Device Configuration Information (Xilinx, Inc.) |
| ISC | iScreensaver Designer Project File (Xochi Media Inc.) |
| ISC | Internet Servide Providers Configuration File |
| ISD | dynaSight File |
| ISD | GraphPad InStat |
| ISD | InstallShield Dialog (InstallShield Software Corporation) |
| ISD | RapidFile Dictionary |
| ISF | ModelPress Highly-compressed CAD Model (Informative Graphics Corporation) |
| ISF | Inspiration Concept Map (Flowchart) Document (Inspiration Software, Inc.) |
| ISFF | Intergraph Standard File Format |
| ISH | Compressed Archive File |
| ISH | Image Speeder |
| ISH | Image System |
| ISK | Command File |
| ISL | DB-MAIN Scheme File |
| ISL | Inno Setup 1.3 File |
| ISL | InstallShield Temporary Installer File (InstallShield Software Corporation) |
| ISL | The Universal Game Server Export File (The Universal Development Team) |
| ISM | Image System |
| ISML | Intershop Enfinity |
| ISO | CALS ISO 8613 Bitmap |
| ISO | Easy CD Creator Disc Image (Sonic Solutions) |
| ISO | InstallShield Uninstall File (InstallShield Software Corporation) |
| ISO | ISO-9660 Table |
| ISO | RichWin |
| ISO | SEGA CD/Sony Playstation Game File |
| ISO | Cimagraphi CAD File (Graphitech Ltd) |
| ISO | ISO-9660 CD Disc Image |
| ISO | Virtual PC Virtual CD-ROM Image (Microsoft) |
| ISOD | CloneDVD ISO Image (Elaborate Bytes AG) |
| ISP | IIS Internet Service Provider Settings (Microsoft) |
| ISP | Internet Communication Settings |
| ISP | Internet Sign-up File |
| ISP | Internet/Internationnal Communication Settings parameter file |
| ISR | Go-Moku Game File |
| ISR | Streets & Trips Route File (Microsoft) |
| ISR | Uninstaller Text File |
| ISS | Caseware IDEA IDEAScript |
| ISS | InstallShield Response File (InstallShield Software Corporation) |
| ISS | ISS Graphic |
| ISS | Inno Setup Script (Jordan Russell's Software) |
| ISS | The Longest Journey Sound File (Funcom) |
| IST | Digitrakker Instrument File |
| IST | Imagine Staging Stage Editor File (Impulse, Inc.) |
| IST | IsoStar Library of Intermolecular Interactions |
| IST | TeX MakeIndex Style Index |
| ISTG | Imagine Staging Stage Editor File (Impulse, Inc.) |
| ISTR | IsoStar Library of Intermolecular Interactions |
| ISU | Easy CD Creator 4 Uninstall File |
| ISU | InstallShield Uninstall Script (InstallShield Software Corporation) |
| ISU | Netscape File |
| IT | Impulse Tracker Music Module |
| IT | Intalk Settings |
| IT | Read.it |
| IT | Sound |
| IT3 | Internet Timer 3 Log File |
| ITA | Italian README File |
| ITA | Personal Paint Italian Language User Interface File (Amiga) |
| ITC | Uthscsa Imagetool Calibration File |
| ITE | E-Tabs Reader File |
| ITF | Inside Tract File |
| ITF | JPI TopSpeed Pascal Interface File |
| ITG | Intergraph Format |
| ITH | InTether Receiver File (Infraworks Corporation) |
| ITHMB | iPod photo Thumbnail Image (Apple Computer, Inc.) |
| ITI | Impulse Tracker Instrument |
| ITL | iTunes Music Database File (Apple Computer, Inc.) |
| ITM | Infinity Game Engine Inventory Object (BioWare Corp.) |
| ITM | Item / Article / Zone |
| ITM | Diablo II Item (Blizzard Entertainment) |
| ITP | riteMail Mail and Notes File (Pen&Internet, LLC) |
| ITR | IntroCreator Project File (Klaus Schwenk) |
| ITR | Icy Tower Replay (Johan Peitz, Free Lunch Design) |
| ITS | Impulse Tracker Sample |
| ITS | International Translation |
| ITS | Internet Document Set |
| ITU | Sheffield Dictionary File |
| ITW | Icetips Wizard Editor |
| ITW | IT Works Database (Simple Solutions) |
| ITX | Igor Chromatogram File |
| ITX | Impulse Imagine for Windows |
| ITX | ISB Raw Song Format |
| ITX | ITRANS Multilingual Transliteration Scheme |
| ITX | Texture IMAGINE |
| ITZ | Amiga and PC Tracker Module |
| ITZ | Impulse Tracker Music Module |
| IUM | infoUSA Network Meter File (infoUSA.com, Inc.) |
| IV | Open Inventor File |
| IV | VRML File |
| IV-VRML | Inventor VRML Format Document |
| IVB | Truevision Targa Format Bitmap |
| IVC | iView MediaPro Catalog (iView Multimedia Ltd.) |
| IVD | Beyond 20/20 Microdata Dimension or Variable-level File |
| IVD | ISPS for Windows Multi-dimensional Data Store (International Planning & Research Corporation) |
| IVF | Indeo Video File (Intel Corporation) |
| IVI | MSDN InfoViewer 5.0 Topic (Microsoft) |
| IVN | iView MediaPro Catalog Notepad File (iView Multimedia Ltd.) |
| IVNU | Inetba Web Page (Inetba) |
| IVP | Beyond 20/20 User Subset Profile |
| IVP | Truevision Targa Bitmap |
| IVP | PhotoSuite Ver 4 Image-based Virtual Reality Text File (Sonic Solutions) |
| IVQ | MSDN InfoViewer 5.0 index full-text searches |
| IVR | Virtual Reality World Live Picture |
| IVS | iVisit |
| IVS | ImageView Storage File (Infinite Solutions) |
| IVS | ISPS for Windows Settings File (International Planning & Research Corporation) |
| IVT | Beyond 20/20 Table |
| IVT | Concordance Inverted Full Text Database File |
| IVT | MSDN InfoViewer 5.0 Information Title |
| IVU | IVUE Live Picture Drawing |
| IVUE | Live Picture Multi-view Format |
| IVWD | IntelliVIEW Designer Data/Layout File (Synaptris; products division of Cybernet Software Systems, Inc.) |
| IVWL | IntelliVIEW Designer Report Layout File (Synaptris; products division of Cybernet Software Systems, Inc.) |
| IVWR | IntelliVIEW Offline Report File (Cybernet Software Systems Inc.) |
| IVWR | IntelliVIEW Designer Report File (Synaptris; products division of Cybernet Software Systems, Inc.) |
| IVX | Beyond 20/20 Extract |
| IW | IBM Updater File |
| IW | IconAuthor - HSC InterActive Presentation Flowchart |
| IW | Iconware Application |
| IW | Idlewild Screensaver |
| IW4 | DjVu File |
| IWA | IBM Writing Assistant Text |
| IWC | Installwatch Database |
| IWC | WaveL Wavelet Compressed Bitmap (WaveL Software) |
| IWI | Ignite Image Optimiser |
| IWM | IconAuthor Start File (AimTech Corp) |
| IWP | Wang Text File |
| IWP | InfinityQS SPC Web Publishing Configuration (InfinityQS International) |
| IWR | i*write 2.0 File |
| IWR_BAK | i*write 2.0 Backup File |
| IWS | InstallWatch Scan Results (Epsilon Squared) |
| IWZ | ItemWizard File |
| IX | FrameMaker Index File (Adobe) |
| IX | Modula-3 Linker Information |
| IX | PaperPort Search File (ScanSoft Inc.) |
| IX | WordPerfect Office Template File (Corel Corporation) |
| IX | WordPerfect Office Template File (Corel Corporation) |
| IX1 | Rebel Chess Program Database File |
| IX2 | Rebel Chess Program Database File |
| IX2 | WordPerfect Office Template File (Corel Corporation) |
| IX2 | WordPerfect Office Calendar File Calendar File (Corel Corporation) |
| IX3 | Rebel Chess Program Database File |
| IX3 | Instant.EXE 3.0 Script (ASXperts Inc.) |
| IX4 | Rebel Chess Program Database File |
| IXA | Ulead Image File |
| IXB | Ulead Video Image File (Ulead Systems, Inc.) |
| IXC | ArcView Geocoding Index For Read-Write Coverages (ESRI) |
| IXC | Index+ for Windows Code Definition File (System Simulation Ltd.) |
| IXE | InterEX Control File |
| IXF | IFX for FAX FAX Document |
| IXF | Index+ for Windows Form Defintion File (System Simulation Ltd.) |
| IXL | DB/TextWorks Database Indexed List |
| IXP | ISIPublisher Publication Information Export (Image Solutions, Inc.) |
| IXR | Index+ for Windows Report Definition File (System Simulation Ltd.) |
| IXS | ArcView Geocoding Index For Read-Write Shapefiles (ESRI) |
| IXT | ISIPublisher Publication Template (Image Solutions, Inc.) |
| IXX | C++ Include File |
| IZD | Intrexx Application Export Format |
| IZS | 1st Page 2000 JavaScript Example File (Evrsoft) |
| IZT | IZL Binary Token |
| IZX | Intermezzon Designer E-Learning Published File (Intermezzon Learning Systems AB) |
| I_I | Eru/erd File |