How to Fix Wmasf.dll Not Found or Missing Errors

If reinstalling the program that uses this DLL file doesn't fix the error, run the System File Checker tool

Wmasf.dll errors are caused by situations that lead to the removal or corruption of wmasf.dll, the Windows Media ASF DLL file. In some cases, wmasf.dll errors could indicate a registry problem, a virus or malware issue, or even a hardware failure.

The wmasf.dll error message could apply to any program or system that might utilize the file on any of Microsoft's operating systems, including Windows 11, Windows 10, Windows 8, Windows 7, Windows Vista, Windows XP, and Windows 2000.

Wmasf.dll Errors

Wmasf.dll error message in Windows

There are several ways wmasf.dll errors can show up on your computer. Here are some of the more common error messages you might see:

  • Wmasf.dll Not Found
  • This application failed to start because wmasf.dll was not found. Re-installing the application may fix this problem.
  • Cannot find [PATH]\wmasf.dll
  • The file wmasf.dll is missing.
  • Cannot start [APPLICATION]. A required component is missing: wmasf.dll. Please install [APPLICATION] again.
  • MovieMaker.exe - System error. The program can't start because wmasf.dll is missing from your computer. Try reinstalling the program to fix this problem.
  • C:\Windows\system32\WMASF.dll is either not designed to run on Windows or it contains an error.

These error messages might appear while using or installing certain programs, when Windows starts or shuts down, or maybe even during a Windows installation.

Since the file is associated with the Media Feature Pack, there's a good chance the error is produced in the context of a media player application.

The context of the error is an important piece of information that will be helpful while solving the problem.

How to Fix Wmasf.dll Errors

Follow these steps in the order they're given below to try the simpler solutions first.

Do not download wmasf.dll from a "DLL download" website. There are many reasons why downloading a DLL file like that is a bad idea. If you need a copy of this file, it's best to obtain it from its original, legitimate source.

  1. Restore wmasf.dll from the Recycle Bin. The easiest possible cause of a "missing" wmasf.dll file is that you've mistakenly deleted it.

    If you suspect that you've accidentally deleted wmasf.dll but you've already emptied the Recycle Bin, you may be able to recover wmasf.dll with a free file recovery program.

    Start Windows in Safe Mode to complete this step, or any of the following steps, if you're unable to access Windows normally due to the error.

  2. Use System Restore to undo recent system changes. If you suspect that the wmasf.dll error was caused by a change made to an important file or configuration, System Restore could solve the problem.

  3. Reinstall the program that uses the wmasf.dll file. If the wmasf.dll DLL error occurs when you use a particular program, reinstalling the program should replace the file.

    If you're getting the "MovieMaker.exe" error, try reinstalling Windows Essentials, which is the suite that Movie Maker is a part of. Be sure to remove the current installation with a tool like IObit Uninstaller to ensure that it's completely gone, and then use this link to download Windows Essentials (that's a direct link to the EXE file).

    Try your best to complete this step. Reinstalling the program that provides the wmasf.dll file, if possible, is a likely solution to this DLL error.

  4. Run the sfc /scannow System File Checker command to replace a missing or corrupt copy of the wmasf.dll file. This DLL file is provided by Microsoft, so the System File Checker tool should restore it.

  5. Run a virus/malware scan of your entire system. Some wmasf.dll errors could be related to a virus or other malware infection on your computer that has damaged the DLL file. It's even possible that the wmasf.dll error you're seeing is related to a hostile program that's masquerading as the file.

  6. Update the drivers for hardware devices that might be related to wmasf.dll. If, for example, you're receiving a "The file wmasf.dll is missing" error when you play a 3D video game, try updating the drivers for your video card.

    The wmasf.dll file may or may not be related to video cards—this was just an example. The key here is to pay very close attention to the context of the error and troubleshoot accordingly.

  7. Roll back a driver to a previously installed version if wmasf.dll errors began after updating a particular hardware device's driver.

  8. Install any available Windows updates. Many service packs and other patches replace or update some of the hundreds of Microsoft distributed DLL files on your computer. The wmasf.dll file could be included in one of those updates.

  9. Test your memory and then test your hard drive. We've left the majority of hardware troubleshooting to the last step, but your computer's memory and hard drive are easy to test and are the most likely components that might cause wmasf.dll errors as they fail.

    If the hardware fails any of your tests, replace the memory or replace the hard drive as soon as possible.

  10. Repair your installation of Windows. If the individual wmasf.dll file troubleshooting advice above is unsuccessful, performing a startup repair or repair installation should restore all Windows DLL files to their working versions.

  11. Use a free registry cleaner to repair wmasf.dll related issues in the registry. A free registry cleaner program may be able to help by removing invalid wmasf.dll registry entries that might be causing the DLL error.

    This is more of a "last resort" attempt before the destructive step coming up next. Using a registry cleaner is only helpful in really specific situations—learn more in our Registry Cleaners FAQ.

  12. Perform a clean installation of Windows. This will erase everything from the hard drive and install a fresh copy of Windows. If none of the steps above correct the wmasf.dll error, this should be your next course of action.

    All the information on your hard drive will be erased during this step. Make sure you've made the best attempt possible to fix the wmasf.dll error using a troubleshooting step prior to performing a clean install.

  13. Troubleshoot for a hardware problem if any wmasf.dll errors persist. After a clean Windows installation, your DLL problem can only be hardware related.

Need More Help?

If you're not interested in fixing this problem yourself, see How Do I Get My Computer Fixed? for a full list of your support options, plus help with everything along the way like figuring out repair costs, getting your files off, choosing a repair service, and a lot more.

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