While searching for an answer to the question - How to open the DEF file? - you probably found websites, which offer software that was able to open any file extension. Do not be fooled, there is no one program that will allow you to work with any file extension, including the DEF file. Each program contains a different type of data and you need specialized software to properly work with the DEF file. Here is a list of programs that are designed to work with the DEF file - remember, these applications are able to open at most a few file extensions, they are designed to work with a specific data type.
| File type | Definition Format |
| Developer | Lack of information |
| Popularity | |
| Share |
If after installing the program from a list, you still cannot open a file with the DEF extension, the reason may be that the file is damaged. The solution may be to find a new copy of the DEF file you want to open
In this case, the easiest way is to use the tool built into the operating system for association of the DEF file with applications to support it. Double click on the file you cannot open - the operating system will display a list of programs that are likely to work with your DEF file. Choose one of them, or select the location on a disk where you installed one of the applications from our list. Windows should then open the DEF file using the program installed earlier.
Entries containing links of the DEF file extensions with applications is located in the HKEY_CLASSES_ROOT. If you do not know how to get to the Windows Registry, or how to make changes in it, ask a specialist for help. Lack of knowledge on the subject may cause irreversible changes on your computer.
There may be a situation when a computer virus passes itself off as the DEF file. In this case, such a file will definitely not be opened. Download a good antivirus program and scan the DEF file mentioned. If the antivirus application detects malicious data, it may signify that the DEF file is infected.
| DESKTOP | DesktopX Windows Desktop Theme Format |
| DEL | Apple Safari |
| DEK | Magic The Gathering Deck Format |
| DEPLOYMENTOPTIONS | SQL Server Deployment Options |
| DES | CorelDRAW Corel Designer Technical Illustration Format |
| DESC | Description Format |
| DESKTHEMEPACK | Microsoft Windows 8 Theme Pack Format |
| DESCRIPTION | Multilizer PDF Translator Description |
| DEZ | DeZign For Databases Project |
| DEP | Microsoft Visual Basic Setup Wizard Dependency Format |
