How To Open DEF FilesReader Question: "Hi Wally, I am having problems opening DEF Files and wondering how to fix it?" - Brian D., New York
- Step 1 : Download PC Repair & Optimizer Tool (3.32 MB) (WinThruster for Win 10, 8, 7, Vista, XP and 2000 - Microsoft Gold Certified).
- Step 2 : Install the software (30 seconds). After installing, an automatic scan will begin to find registry issues that could be causing PC problems.
- Step 3 : After the scan completes (15 seconds), click "Fix Issues" to repair all registry problems.
What Are DEF Files?DEF files are Developer Files primarily associated with . (Other files may also be using the DEF file extension. If you know of any other software using the DEF file extension, please contact us so that we can update our information accordingly.)
Opening DEF FilesThe easiest way to open a DEF file is by double-clicking on it, which will let the computer decide the best way to open it according to the Windows DEF file association settings. If your computer opens your DEF file, but it's the incorrect application, you'll need to change your Windows registry file association settings. In other words, Windows is associating DEF file extensions with the wrong software program.
Is Your PC Healthy?I always recommend to my readers to regularly use a trusted registry cleaner and optimizer such as WinThruster (Download) or CCleaner. Many problems that you encounter can be attributed to a corrupt and bloated registry. Happy Computing! :)
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