How to fix
Winmm.dll missing or not found error
on Windows

I've been been experiencing the "winmm.dll missing" error for quite a while now. It all started when I upgraded to Windows 11. Is there something I can do?

The winmm.dll not found error is really frustrating, and it may occur when running specific programs or games on a computer with Windows. Normally, the error occurs because of issues connected with the winmm.dll file. This file is an important component of the Windows Multimedia API. Essentially, it could be corrupted, misplaced, or missing altogether. As this file plays a very critical role in managing audio and other multimedia activities, its absence can cause an issue for applications utilizing these functionalities.

The reason this Winmm.dll missing error occurs can be manifold. Most of the reasons are software-related or related to system files. Sometimes, it happens when a program fails to find its required DLL file. Some other causes are corruption in system files, incomplete installations of a program, or virus infection. It is probable that the recent update to Windows or a change in hardware has, somewhere, affected the location or integrity of the file. 

This error frequently appears when users attempt to open software that depends on multimedia functions. For instance, games or media playback tools often require winmm.dll to run smoothly. The message displayed on the screen might vary slightly, but it typically says: 

• "Winmm.dll is missing." 
• "Winmm.dll not found." 
• "The program can't start because winmm.dll is missing from your computer." 

 Without the winmm.dll file, programs relying on multimedia features may fail to function correctly. This can result in application crashes or limited performance, particularly in cases where audio or video playback is integral to the software. Ignoring the issue might also lead to broader system instability, as certain background processes in Windows may depend on this DLL file to operate. 

While resolving the winmm.dll missing error often involves straightforward troubleshooting steps, it's important to avoid downloading DLL files from untrusted third-party sources. Such files may contain malware or might not be compatible with your system, potentially worsening the problem. Instead, focus on solutions that repair or restore the file securely. 

If the issue persists despite attempts to resolve it manually, you may benefit from using an automatic repair and maintenance tool like [d1]. This software can address system file corruption, repair damaged DLLs, and resolve other Windows-related issues with minimal effort.

Fix 1. Restart your computer

A simple restart can often resolve the winmm.dll missing or not found error by refreshing your system and ensuring all required files load properly during boot.

• Click on the Start menu.
• Click on Power button and select Restart.
• Wait for your computer to restart.

Fix 2. Check for Windows updates

Updating your system can resolve the error if it’s caused by outdated or missing system components.

• Type Updates in the Windows search bar and press Enter.
• The new window will open and you should be notified about available updates - click Install all.
• If none are available, click Check for updates, and they should be installed automatically.
• Don't forget to install all the available optional updates.
• When done, restart your system.

Fix 3. Run a malware scan

Malware infections can corrupt or remove essential DLL files like winmm.dll. A full system scan can help identify and resolve such issues. You can use Microsoft Safety Scanner, employ a reputable third-party app, or use the built-in Defender offline scan:

• Type Windows Security in the Windows search bar and hit Enter.
• Select Virus & threat protection.
• Pick Scan options.
• Choose Microsoft Defender Offline scan and click Scan now.
• Your computer will immediately restart and begin a deep scan.

Fix 4. Use SFC and DISM

• Type cmd in Windows search.
• Right-click on Command Prompt and selecy the Run as administrator option.
• When User Account Control shows up - click Yes.
• Then, copy and paste the following command, pressing Enter after:
  sfc /scannow
• Wait till the scan is finished. If Windows finds system file integrity violations, it will attempt to fix them. After this, use the set of the following commands, pressing Enter each time:
  DISM /Online /Cleanup-Image /CheckHealth
  DISM /Online /Cleanup-Image /ScanHealth
  DISM /Online /Cleanup-Image /RestoreHealth
  Note: if you get an error executing this last command, add /Source:C:\RepairSource\Windows /LimitAccess to it and try again.
• Close down the Command Prompt and restart your system.

Fix 5. Reinstall the problematic application

If the error appears for a specific app, reinstalling it can replace any missing dependencies.

• Uninstall the application causing the error.
• Download the latest version from the official website.
• Reinstall the application and check if the issue persists.

Fix 6. Reregister the DLL file

If the file is missing, reregistering it can resolve the error.

• Open Command Prompt as administrator.
• Type in the following commands and press Enter after each:
  regsvr32 /winmm.dll
  regsvr32 winmm.dll
• Close down everything and restart your computer.

Fix 7. Update your audio drivers

Outdated or corrupted audio drivers can trigger errors related to winmm.dll.

• Right-click on Start and select Device Manager.
• Expand the Sound, video, and game controllers section.
• Right-click your audio device and select Update driver.
• Choose Search automatically for drivers.
• Follow the on-screen instructions to complete the update.
• Restart your computer after the update is installed.

Fix 8. Perform a System Restore

If the issue started recently, restoring your system to an earlier point can help.

• Type in Create a Restore point in Windows search and hit Enter.
• Go to the System Protection tab and pick System Restore.
• Click Next.
• Click Show more restore points (if available).
• Pick the time before the problem occurred and click Next.
• Follow the prompts to finish the process.

Fix 9. Reset Windows

As a last resort, resetting your operating system can resolve the error by reinstalling Windows and restoring default settings.

• Click on Start and pick Settings.
• Go to Windows Update/Update & Security.
• Select Advanced options.
• Under Additional options, select Recovery.
• Under Recovery options, click Reset PC.
• Select the option to Keep your files and then press Cloud download.
• Follow on-screen instructions to finish the process.