.??_ Files ending in "_" are often compressed install files of the same
name (e.g., .EX_ expands to .EXE, .DL_ expands to .DLL, etc.)
.I Progress Include File
Borland C++ Intermediate File
INTERCAL File (INTERCAL=Compiler Language With No Pronounceable Acronym)
.I17 Pixel Power Collage [XnView]
.I18 Pixel Power Collage [XnView]
.I2S Invision for mIRC Settings
.I66 Interactive66 Graphic Design Information
.IAF MS Outlook 97 and 2000 E-mail Account Settings
.IAM Autodesk Inventor CAD File
.IAN Sterling Software COOL Business Team Model File Sterling merged with Computer Associates.
.IAP TeamBG File (modify Infinity Engine games)
.IAX IBM Image Access Executive Bitmap
.IB7 Pixel Power Collage [XnView]
.IBA MDE InfoHandler Infobase File
.IBF Instant Backup
.IBM Electronic Arts Deluxe Paint [XnView]
Archdos Compressed File (IBM internal file)
.IBS i2 iBase File
.IBX Interscope BlackBox File (encryption program)
.ICA Citrix File
Image Object Content Architecture (IOCA) Graphics File [XnView]
.ICB Targa Bitmap
Image Capture Board [XnView]
.ICC Kodak Printer Image
IronCAD Catalog
.ICD IronCAD 2D CAD File
ASTi Model Builder File
Rate Structure File (BLDRATE.EXE input)
File Associated with Many Games
.ICE Archive File
.ICF ICOM CS-2100 Radio Programming Data
Insane Chat Saved Conversation [ASCII file] (Use care entering this site)
.ICL Icon Library File (various) ImageForge/IconForge Microangelo [XnView] [IrfanView]
.ICM Image Color Matching Profile File
ICC Profile, Acer Monotor Drive
.ICN Icon Program
AT&T Graphic Format
RIPTerm Image [XnView]
.ICO Icon ImageForge/IconForge Microangelo [IrfanView]
GIMP Icon [GIMP] [XnView]
Sun Icon/Cursor [XnView]
.ICON Sun Icon/Cursor [XnView]
.ICQ ICQ Saved File
.ICS Outlook Calendar File [Buy Office XP at Shop.Microsoft]
SwiftView Command File
IronCAD 3D CAD File
Inovate 3D CAD File
.ICW InterCAD File (Polish site)
.ID Disk Identification File
Lotus Notes ID File
.IDA MS Server File (default.ida is attacked by the Code Red Worm)
.IDB MS Developer Intermediate File
Database Used by Disassembler
.IDC Core IDC [XnView]
.IDD MIDI Instrument Definition
.IDE Integrated Development Environment Configuration File
Sophos Anti-Virus Virus IDEntity File
Borland C++ Project
.IDF MIDI Instruments Drivers File
.IDI i-deas Web ACCESS File
.IDIF Netscape Saved Address Book
.IDL MS Visual C++ Interface Definition File
OMG CORBA Interface Definition Language
.IDQ Internet Data Query File
.IDT Output of DLL2IDT Utility (used in disassembly)
Text Archive Table (used in software development)
.IDV Autodesk Inventor Design View Tree
.IDW Aldus IntelliDraw Vector Graphic
Autodesk Inventor CAD File
.IDX Index (multiple programs)
.IDY Debug Information File (IMS Database related)
.IDZ i-deas Web ACCESS File
.IEF Image File
.IES Photometric File Data [Illuminating Engineering Society]
.IF9 Pixel Power Collage [XnView]
.IFD Jet Form Design Form
.IFF Graphic, Sound (Interchangeable File Format) [XnView] [IrfanView]
The Sims (Maxis) Object/Data File
Sun TAAC Image File [XnView]
.IFM Brighterion iPrevent Fraud Model
.IFO DVD Info File (contains menus and other information)
.IFP KnowledgeMan Script
.IFS OS/2 Warp Installable File System
IconForge Image EXE Library
Yuvpak Compressed Fractal Image
.IFW Luminosity Impact! File
.IFX ImageSoft v2.00 Graphic
.IGES IGES-Format [IGES Info]
.IGF Inset Systems Metafile
.IGNORE Likely a text file (e.g., README.IGNORE)
.IGP Igor Reader Sheet Music File
.IGR Intergraph SmartSketch Drawing
.IGS IGES-Format [IGES Info]
.IGX iGrafx Process (graphical process modeling and simulation)
.II C64 Doodle Compressed File [XnView]
.IIF QuickBooks for Windows Interchange File
.III Intel Phone Compatible
.IIM Interscope InstallMaster Setup Project
Inshape Graphic [XnView]
iOpus Internet Macro
.IIMG Interleaf Graphic [XnView]
.IJS Text File
File Often Associated with J.EXE (not certain what J.EXE does)
.IKL MS InkBall (accessory for Windows XP Tablet PC Edition - due end 2002)
.IL Icon Library
MSIL Assembler Input File
.ILB Scream Tracker Data
.ILBM Graphic, Sound (Interchangeable File Format) [may be .IFF file, see above]
.ILK MS ILink Program Format Outline
.ILL Adobe Illustrator Prologue
.ILM Satsang Quiz File
CAS 200 QDA v3.0 Image List Mode File (DNA mapping)
Illuminatus Opus Multimedia File
Iomega Zip Drive Speed Configuration File [Good Info Source]
.ILPLOPTIONS InterLock and PowerLock (public computer management utility)
.ILPLVOUCHERS InterLock and PowerLock (public computer management utility)
.ILV ILOG View File
.ILVG iLiving P-to-P (iliving file viewer)
.IM5 Visilog [XnView]
.IM8 Sun Raster Graphic
.IMA WinImage File (Floppy and disk imager)
Mirage Vector Graphics
.IMB IncrediMail File
.IMC IncrediMail File
.IMF ImageForge/ImageForge Image EXE Library
IncrediMail Letter
.IMG Bitmap Graphic (several programs) [XnView] [IrfanView]
AutoCAD CAD-Camera [XnView]
ERDAS IMAGINE Format
Planetary Data System [XnView]
Idrisi32 Raster Image
Radiance Scene Description Image [XnView]
CloneCd Related File
Floppy Image File
Apple Macintosh Disk Copy Format
Microtek Eyestar [XnView]
Sharp GPB [XnView]
Starbase [XnView]
Vicar [XnView]
Vivid Ray-tracer [XnView]
.IMI IncrediMail Animation
.IMJ JFIF File With a MS Windows BMP Header (Pegasus Image Corporation)
.IMM IncrediMail Trash
.IMN IncrediMail Notifier
.IMP Urban Chaos Game File
Lotus Improv Spreadsheet
Babya Installer Archive
DVD File
FileMaker Database Translation Filter
WinIMP Archive
.IMQ ImageQ Presentation
.IMR Cognos Impromptu Report Writer
.IMS Incredimail Graphic
.IMT IMNET Image [XnView]
.IMV Yahoo Instant Messenger IMVironment
.IMW Imageware Surfacer 3D CAD Surface Geometry
IncrediMail Sound
.IMY iMelody Ringtone Format (link is PDF file)
.IMZ Compressed Floppy Image
WinImage File (Floppy and disk imager)
.IN$ HP NewWave Install File
.IN3 Harvard Input Device Driver (Harvard Graphics taken over by Serif)
.INB Vermont HighText Script
Visual Expert Source Code Documentation
.INC Include File (various)
Internet Connection File (used by ISPs)
.INCD Adobe InCopy/InDesign Link File (Link stories from an InDesign document)
.IND dBase IV or DataPerfect Index
Well of Souls Game File
.INDD Adobe Indesign Document
.INF Information or Setup File (many)
.INFO Amiga Information File [XnView]
.INI Initialization/Configuration File (many)
.INK Pantone Reference File
Mimio Ink File [Electronic Whiteboard]
.INL MS Visual C++ Inline Function File
.INP Oracle Source Code
Self-Extracting Archive Utility Project
GIS Software Text Input File [GIS info]
(ArcView, et.al.) (JShape/FShape)
.INS Internet Communication Setting
AdLib Instrument Music File
WordPerfect File
Ensoniq EPS Family Instrument
Sample Cell / II Instrument
InstallShield Script
X-Internet Sign-up File
Inspiration Mind Mapping Software File
1st Reader Install Script
.INSTALL Likely a text file (e.g., README.INSTALL)
.INT Borland Interface Units
Foxpro Code Page
Signature Semi-compiled Program
Unreal Tournament Mutator
Intermediate Code used for syntax checking (various)
.INTER Interspector Project File
.INTERLOCKFAVOURITES InterLock and PowerLock (public computer management utility)
.INTO Interspector Object File
.INU INSPEC Configuration File
.INX Foxbase Index
ACL For Windows Index (data mining software)
.IO Compressed Archive
.IOB Imagine File
TDDD Format 3D Graphic Database
.IOC Instant ORGcharting! Organization Chart
.IOCA Image Object Content Architecture (IOCA) Graphics File [XnView]
.IOF Findit Document
.ION Text Program/Installation Description
4DOS File Description
.IP IconPackager File (changes the look of Windows icons)
.IPD InstallPROG 6 EDBS Install Database
.IPF Microsoft SMS Installer Script (with System Management Server 2.0)
.IPG Mindjongg Format [XnView]
.IPH InterPaint Hires Image [XnView]
.IPK NRG iPack File
.IPL Corel Pantone Spot Reference Palette
InstallPROG 6 EDBS File Library
.IPR IntelliJ Project XML File
.IPS Game Patch File (allows running of illegal copies of some games)
.IPT Autodesk Inventor CAD File
InterPaint Multicolor Image [XnView]
.IPW UniPlot Graph [Free viewer]
.IPX Interactive Pictures Corporation AV File
.IPZ ICQ Skin
.IQF Integra 3.0 Query File
.IQY Excel Web Query [Buy Office XP at Shop.Microsoft]
.IRD MS Money Temporary File
.IRIS Silicon Graphics RGB [XnView]
.IRS WordPerfect Resource File
.ISD RapidFile Dictionary
GraphPad InStat
InstallShield Dialog
.ISH Compressed Archive File
Image Speeder [XnView]
Image System (HiRes) [XnView]
.ISK Command File (similar to a batch file - view in text editor)
.ISL InstallShield Temporary Installer File
.ISM Image System (Multicolor) [XnView]
.ISO File List for CD-ROM [Fantom CD Emulator]
ISO Buster File
InstallShield Uninstall File
ISO-9660 Table
Easy CD Creator Disc Image
.ISP Internet Sign-up File
Internet Communication Settings
.ISR MS Streets & Trips Route File
Uninstaller Text File (_deisreg.isr)
.ISS InstallShield Response File
ISS Graphic [XnView]
.IST Digitrakker Instrument File (by n-FaCToR)
.ISU InstallShield Uninstall Script
Easy CD Creator 4 Uninstall File
Netscape File
.IT Impulse Tracker Music Module
Intalk Settings
.ITE E-Tabs Reader File
.ITF Inside Tract File
JPI TopSpeed Pascal Interface File
.ITG Intergraph Format [XnView]
.ITH InTether Receiver File (security software)
.ITI Impulse Tracker Instrument
.ITM Infinity Engine Game Item
.ITS Internet Document Set
Impulse Tracker Sample
.ITW Icetips Wizard Editor (partially encrypted ini file)
.IV VRML File
Open Inventor File
.IVF Indeo Video File
.IVP Truevision Targa Bitmap [XnView]
.IVT Beyond 20/20 Table (Multidimensional data viewer)
Concordance Inverted Full Text Database File
.IVX Beyond 20/20 Extract (Multidimensional data viewer)
.IW Iconware Application
Idlewild Screensaver
.IW4 DjVu File [XnView]
.IWA IBM Writing Assistant Text
.IWI Ignite Image Optimiser
.IWC Installwatch Database (install monitor)
.IWP Wang Text File
.IWR i*write 2.0 File
.IWR_BAK i*write 2.0 Backup File
.IX Framemaker Index File
Paperport Search File
.IZD Intrexx Application Export Format (binary)
.IZT Izl Binary Token
