FILExt - The File Extension Source

Details for file extension .DEF are on this page. Because there is no central registry for file extensions and their associated programs there may be multiple entries on this page. And, because there are many (some say over a million) such associations not all may be listed here.

TIP: Click here to run a FREE scan for .DEF related errors.

Windows can't open .DEF files?
If Windows is unable to open files with the extension .DEF you may not have the appropriate program installed or, you may have registry errors. To help, we strongly recommend you run this free registry scan.

A search on the file extension you submitted shows 21 record(s). The details for each of these are shown below. The best FILExt can do for you is provide the details we know about. Selecting the information that applies to your particular situation is up to you. Use any hints provided. If the information here is not helpful, FILExt is sorry; but as a research site FILExt cannot provide personal support. If you need further information you might try the research tips on the FILExt Help Me page.

Extension: DEF
Program and/or Extension Function [What's This?]		Company [What's This?]
3D Fassade Plus Define Module
Specific Notes [What's This?]
(None) Recommended: Find DEF errors now.
MIME Type [What's This?]	File Classification [What's This?]	Associated Links [What's This?]
		None
Identifying Characters [What's This?]
(None or Unknown)
Program ID [What's This?]
(None or Unknown)
General Notes [What's This?]
(None)
This is record 3086 last modified on 2003-01-14 and created on 2003-01-14.

Extension: DEF
Program and/or Extension Function [What's This?]		Company [What's This?]
ADS Source Code		Autodesk, Inc.
Specific Notes [What's This?]
(None) Recommended: Find DEF errors now.
MIME Type [What's This?]	File Classification [What's This?]	Associated Links [What's This?]
		None
Identifying Characters [What's This?]
(None or Unknown)
Program ID [What's This?]
(None or Unknown)
General Notes [What's This?]
(None)
This is record 3087 last modified on 2005-03-28 and created on 2003-01-14.

Extension: DEF
Program and/or Extension Function [What's This?]		Company [What's This?]
AniSprite		CompuPhase
Specific Notes [What's This?]
(None) Recommended: Find DEF errors now.
MIME Type [What's This?]	File Classification [What's This?]	Associated Links [What's This?]
		None
Identifying Characters [What's This?]
(None or Unknown)
Program ID [What's This?]
(None or Unknown)
General Notes [What's This?]
Note: This entry has not yet been verified by FILExt. It was submitted to the list and appeared to be accurate; however, no verification links have so far been found on the Internet. Please use this association data with that in mind.
This is record 3088 last modified on 2003-01-14 and created on 2003-01-14.

Extension: DEF
Program and/or Extension Function [What's This?]		Company [What's This?]
ArcView Defaults File		ESRI
Specific Notes [What's This?]
ODB Format (North Arrows, Layout Templates, etc) Recommended: Find DEF errors now.
MIME Type [What's This?]	File Classification [What's This?]	Associated Links [What's This?]
		GIS Info
Identifying Characters [What's This?]
(None or Unknown)
Program ID [What's This?]
(None or Unknown)
General Notes [What's This?]
(None)
This is record 3089 last modified on 2004-06-23 and created on 2003-01-14.

Extension: DEF
Program and/or Extension Function [What's This?]		Company [What's This?]
Bert's Dinosaurs File
Specific Notes [What's This?]
(None) Recommended: Find DEF errors now.
MIME Type [What's This?]	File Classification [What's This?]	Associated Links [What's This?]
		None
Identifying Characters [What's This?]
(None or Unknown)
Program ID [What's This?]
(None or Unknown)
General Notes [What's This?]
(None)
This is record 3090 last modified on 2003-01-14 and created on 2003-01-14.

Extension: DEF
Program and/or Extension Function [What's This?]		Company [What's This?]
C++ Definition
Specific Notes [What's This?]
(None) Recommended: Find DEF errors now.
MIME Type [What's This?]	File Classification [What's This?]	Associated Links [What's This?]
		None
Identifying Characters [What's This?]
(None or Unknown)
Program ID [What's This?]
(None or Unknown)
General Notes [What's This?]
(None)
This is record 3091 last modified on 2003-01-14 and created on 2003-01-14.

Extension: DEF
Program and/or Extension Function [What's This?]		Company [What's This?]
Data Entry/Review Module		DATAIR Employee Benefit Systems, Inc.
Specific Notes [What's This?]
Defines Data Entry forms. Recommended: Find DEF errors now.
MIME Type [What's This?]	File Classification [What's This?]	Associated Links [What's This?]
		None
Identifying Characters [What's This?]
(None or Unknown)
Program ID [What's This?]
(None or Unknown)
General Notes [What's This?]
(None)
This is record 15590 last modified on 2004-01-02 and created on 2004-01-02.

Extension: DEF
Program and/or Extension Function [What's This?]		Company [What's This?]
DbForm Document Definiton		Version One Ltd
Specific Notes [What's This?]
DbForm is an enterprise-wide white-paper printing solution, which automatically prints high quality business documents directly from core business applications onto plain paper on laser printers. This file is a script describing the creation of a PCL document. Recommended: Find DEF errors now.
MIME Type [What's This?]	File Classification [What's This?]	Associated Links [What's This?]
		None
Identifying Characters [What's This?]
(None or Unknown)
Program ID [What's This?]
(None or Unknown)
General Notes [What's This?]
(None)
This is record 26249 last modified on 2008-12-29 and created on 2008-12-29.

Extension: DEF
Program and/or Extension Function [What's This?]		Company [What's This?]
Defaults
Specific Notes [What's This?]
(None) Recommended: Find DEF errors now.
MIME Type [What's This?]	File Classification [What's This?]	Associated Links [What's This?]
		None
Identifying Characters [What's This?]
(None or Unknown)
Program ID [What's This?]
(None or Unknown)
General Notes [What's This?]
(None)
This is record 3092 last modified on 2003-01-14 and created on 2003-01-14.

Extension: DEF
Program and/or Extension Function [What's This?]		Company [What's This?]
Definitions
Specific Notes [What's This?]
(None) Recommended: Find DEF errors now.
MIME Type [What's This?]	File Classification [What's This?]	Associated Links [What's This?]
		None
Identifying Characters [What's This?]
(None or Unknown)
Program ID [What's This?]
(None or Unknown)
General Notes [What's This?]
(None)
This is record 3093 last modified on 2003-01-14 and created on 2003-01-14.

Extension: DEF
Program and/or Extension Function [What's This?]		Company [What's This?]
Geoworks Assembly Header File
Specific Notes [What's This?]
(None) Recommended: Find DEF errors now.
MIME Type [What's This?]	File Classification [What's This?]	Associated Links [What's This?]
		None
Identifying Characters [What's This?]
(None or Unknown)
Program ID [What's This?]
(None or Unknown)
General Notes [What's This?]
(None)
This is record 3094 last modified on 2003-02-08 and created on 2003-01-14.

Extension: DEF
Program and/or Extension Function [What's This?]		Company [What's This?]
Modula-2 Definition Module File
Specific Notes [What's This?]
(None) Recommended: Find DEF errors now.
MIME Type [What's This?]	File Classification [What's This?]	Associated Links [What's This?]
		None
Identifying Characters [What's This?]
(None or Unknown)
Program ID [What's This?]
(None or Unknown)
General Notes [What's This?]
(None)
This is record 3095 last modified on 2003-01-14 and created on 2003-01-14.

Extension: DEF
Program and/or Extension Function [What's This?]		Company [What's This?]
Module Definition/Configuration File
Specific Notes [What's This?]
(None) Recommended: Find DEF errors now.
MIME Type [What's This?]	File Classification [What's This?]	Associated Links [What's This?]
		None
Identifying Characters [What's This?]
(None or Unknown)
Program ID [What's This?]
(None or Unknown)
General Notes [What's This?]
Note: This entry has not yet been verified by FILExt. It was submitted to the list and appeared to be accurate; however, no verification links have so far been found on the Internet. Please use this association data with that in mind.
This is record 3096 last modified on 2003-01-14 and created on 2003-01-14.

Extension: DEF
Program and/or Extension Function [What's This?]		Company [What's This?]
OPTLINK Digital Mars Module Definition File		Digital Mars
Specific Notes [What's This?]
OPTLINK, the Digital Mars linker, links object files and libraries to produce an executable program or DLL for DOS, Windows 3.x, or Win32. The .DEF file describes the essential characteristics of an application or library for Win16 or Win32. It also assigns segment sequences, function orders for encapsulated functions, and so on, even in conventional DOS .EXE files. Recommended: Find DEF errors now.
MIME Type [What's This?]	File Classification [What's This?]	Associated Links [What's This?]
		Module Definition Files Described
Identifying Characters [What's This?]
(None or Unknown)
Program ID [What's This?]
(None or Unknown)
General Notes [What's This?]
(None)
This is record 20274 last modified on 2006-09-25 and created on 2006-09-25.

Extension: DEF
Program and/or Extension Function [What's This?]		Company [What's This?]
RCSWin New (Default) Job File		RCS Corporation
Specific Notes [What's This?]
RCSWin is a program for mechanical design, analysis, and cost estimating of shell-and-tube heat exchangers. Recommended: Find DEF errors now.
MIME Type [What's This?]	File Classification [What's This?]	Associated Links [What's This?]
		None
Identifying Characters [What's This?]
(None or Unknown)
Program ID [What's This?]
(None or Unknown)
General Notes [What's This?]
(None)
This is record 26165 last modified on 2008-12-13 and created on 2008-12-13.

Extension: DEF
Program and/or Extension Function [What's This?]		Company [What's This?]
SGML Tag Definition
Specific Notes [What's This?]
(None) Recommended: Find DEF errors now.
MIME Type [What's This?]	File Classification [What's This?]	Associated Links [What's This?]
text/plain		None
Identifying Characters [What's This?]
(None or Unknown)
Program ID [What's This?]
(None or Unknown)
General Notes [What's This?]
(None)
This is record 3097 last modified on 2003-01-14 and created on 2003-01-14.

Extension: DEF
Program and/or Extension Function [What's This?]		Company [What's This?]
SmartWare II Data File
Specific Notes [What's This?]
(None) Recommended: Find DEF errors now.
MIME Type [What's This?]	File Classification [What's This?]	Associated Links [What's This?]
		None
Identifying Characters [What's This?]
(None or Unknown)
Program ID [What's This?]
(None or Unknown)
General Notes [What's This?]
(None)
This is record 3098 last modified on 2003-01-14 and created on 2003-01-14.

Extension: DEF
Program and/or Extension Function [What's This?]		Company [What's This?]
TLink - Wlink - Others Linker Definition
Specific Notes [What's This?]
(None) Recommended: Find DEF errors now.
MIME Type [What's This?]	File Classification [What's This?]	Associated Links [What's This?]
		None
Identifying Characters [What's This?]
(None or Unknown)
Program ID [What's This?]
(None or Unknown)
General Notes [What's This?]
Note: This entry has not yet been verified by FILExt. It was submitted to the list and appeared to be accurate; however, no verification links have so far been found on the Internet. Please use this association data with that in mind.
This is record 3099 last modified on 2003-01-14 and created on 2003-01-14.

Extension: DEF
Program and/or Extension Function [What's This?]		Company [What's This?]
Unknown Apple II File (found on Golden Orchard Apple II CD Rom)
Specific Notes [What's This?]
(None) Recommended: Find DEF errors now.
MIME Type [What's This?]	File Classification [What's This?]	Associated Links [What's This?]
		None
Identifying Characters [What's This?]
(None or Unknown)
Program ID [What's This?]
(None or Unknown)
General Notes [What's This?]
(None)
This is record 21233 last modified on 2006-10-13 and created on 2006-10-13.

Extension: DEF
Program and/or Extension Function [What's This?]		Company [What's This?]
Visual C++ Definition
Specific Notes [What's This?]
(None) Recommended: Find DEF errors now.
MIME Type [What's This?]	File Classification [What's This?]	Associated Links [What's This?]
		None
Identifying Characters [What's This?]
(None or Unknown)
Program ID [What's This?]
(None or Unknown)
General Notes [What's This?]
Note: This entry has not yet been verified by FILExt. It was submitted to the list and appeared to be accurate; however, no verification links have so far been found on the Internet. Please use this association data with that in mind.
This is record 3100 last modified on 2003-01-14 and created on 2003-01-14.

Extension: DEF
Program and/or Extension Function [What's This?]		Company [What's This?]
ZDP ZEBU's Directory Printer Definitions of User-defined Output Formats		ZEBU Informatics
Specific Notes [What's This?]
With ZDP you can export directory entries to other programs or to the clipboard. Recommended: Find DEF errors now.
MIME Type [What's This?]	File Classification [What's This?]	Associated Links [What's This?]
		ZDP Help FAQ
Identifying Characters [What's This?]
(None or Unknown)
Program ID [What's This?]
(None or Unknown)
General Notes [What's This?]
(None)
This is record 15337 last modified on 2003-10-13 and created on 2003-10-13.

System Info for File Extension .DEF

FILExt has been given permission to display the file extension database produced by the Associate This! program. Some of that data has already been included into the main FILExt database; but, not all. Those entries which have not yet been incorporated are shown below in the hope that they will be of some use. Data collected by FILExt on registered file extensions from user systems is also in the display. Be aware this is raw data which may require further research on your part to fully understand. In particular, look at the Program ID. Often a company will put the program's name into the short ID that Windows uses to open registered file extensions. If that's not the case, look at the complete path to the EXE file. Often, programs will install themselves into directories that give either the program or company name. The program name itself may also be used as the EXE file name. These listings are particularly important since they represent listings that are in actual use by users who have sumbitted data to FILExt and therefore these listings can point you to the most likely candidate should there be multiple entries in the FILExt main database.

Program Name and MIME Type Info for File Extension .DEF

FILExt has been given permission to display a Program Name/MIME type database collected by Anthony R. Nemmer. Some of that data has already been included into the main FILExt database; but, not all. Those entries which have not yet been incorporated are shown below in the hope that they will be of some use. Be aware this is raw data which may require further research on your part to fully understand. MIME type listings often contain the name of a program or, at a minimum, a type of file as the leading text in the MIME type.

General Info

• If the extension you are looking for is of the form .??_ the file is likely a compressed file and part of an install routine. When the install program runs it will expand the file and replace the underscore with the proper letter for the file type.
• If the file is sent as an audio file with any three-character extension it may be a dictation file where the extension is the dictator's initials; playable by BCB Voice Systems software (see ??? extension). The file could likewise be a dictation file in TrueSpeech format. Use Windows Sound Recorder and/or Media Player to play these back.
• If the extension you are looking for has a number at the end or is only a number and there were no results consider entering the same extension format using zero or one as some programs produce numbered split files but when the split can be extensive (e.g., .000-.999) only the first entry is in the database.

Need more information about any entries on this page? Try a Google search using terms in the above information along with words like "format," "convert," "conversion," and even "hacking." A search box is provided here for your convenience.

If you have a minute you also might wish to take a survey to get rewards.