Method 1: Copying the Mmstfx.dll Library to the Windows System Directory 

1. The file you will download is a compressed file with the ".zip" extension. You cannot directly install the ".zip" file. Because of this, first, double-click this file and open the file. You will see the library named "Mmstfx.dll" in the window that opens. Drag this library to the desktop with the left mouse button. This is the library you need.

   

2. Copy the "Mmstfx.dll" library and paste it into the "C:\Windows\System32" directory.

   

3. If you are using a 64 Bit operating system, copy the "Mmstfx.dll" library and paste it into the "C:\Windows\sysWOW64" as well.

   NOTE! On Windows operating systems with 64 Bit architecture, the dynamic link library must be in both the "sysWOW64" directory as well as the "System32" directory. In other words, you must copy the "Mmstfx.dll" library into both directories.

   

4. In order to run the Command Line as an administrator, complete the following steps.

   NOTE! In this explanation, we ran the Command Line on Windows 10. If you are using one of the Windows 8.1, Windows 8, Windows 7, Windows Vista or Windows XP operating systems, you can use the same methods to run the Command Line as an administrator. Even though the pictures are taken from Windows 10, the processes are similar.

   1. First, open the Start Menu and before clicking anywhere, type "cmd" but do not press Enter.
   2. When you see the "Command Line" option among the search results, hit the "CTRL" + "SHIFT" + "ENTER" keys on your keyboard.
   3. A window will pop up asking, "Do you want to run this process?". Confirm it by clicking to "Yes" button.

   

5. Paste the command below into the Command Line window that opens up and press Enter key. This command will delete the problematic registry of the Mmstfx.dll library (Nothing will happen to the library we pasted in the System32 directory, it just deletes the registry from the Windows Registry Editor. The library we pasted in the System32 directory will not be damaged).

   %windir%\System32\regsvr32.exe /u Mmstfx.dll

   

6. If the Windows you use has 64 Bit architecture, after running the command above, you must run the command below. This command will clean the broken registry of the Mmstfx.dll library from the 64 Bit architecture (The Cleaning process is only with registries in the Windows Registry Editor. In other words, the dynamic link library that we pasted into the SysWoW64 directory will stay as it is).

   %windir%\SysWoW64\regsvr32.exe /u Mmstfx.dll

   

7. In order to cleanly recreate the dll library's registry that we deleted, copy the command below and paste it into the Command Line and hit Enter.

   %windir%\System32\regsvr32.exe /i Mmstfx.dll

   

8. If the Windows version you use has 64 Bit architecture, after running the command above, you must run the command below. With this command, you will create a clean registry for the problematic registry of the Mmstfx.dll library that we deleted.

   %windir%\SysWoW64\regsvr32.exe /i Mmstfx.dll

   

9. If you did all the processes correctly, the missing dll file will have been installed. You may have made some mistakes when running the Command Line processes. Generally, these errors will not prevent the Mmstfx.dll library from being installed. In other words, the installation will be completed, but it may give an error due to some incompatibility issues. You can try running the program that was giving you this dll file error after restarting your computer. If you are still getting the dll file error when running the program, please try the 2nd method.

Method 2: Copying the Mmstfx.dll Library to the Program Installation Directory 

1. First, you need to find the installation directory for the program you are receiving the "Mmstfx.dll not found", "Mmstfx.dll is missing" or other similar dll errors. In order to do this, right-click on the shortcut for the program and click the Properties option from the options that come up.

   

2. Open the program's installation directory by clicking on the Open File Location button in the Properties window that comes up.

   

3. Copy the Mmstfx.dll library into the directory we opened.

   

4. The installation is complete. Run the program that is giving you the error. If the error is continuing, you may benefit from trying the 3rd Method as an alternative.

Method 3: Uninstalling and Reinstalling the Program that Gives You the Mmstfx.dll Error 

1. Press the "Windows" + "R" keys at the same time to open the Run tool. Paste the command below into the text field titled "Open" in the Run window that opens and press the Enter key on your keyboard. This command will open the "Programs and Features" tool.

   appwiz.cpl

   

2. The Programs and Features screen will come up. You can see all the programs installed on your computer in the list on this screen. Find the program giving you the dll error in the list and right-click it. Click the "Uninstall" item in the right-click menu that appears and begin the uninstall process.

   

3. A window will open up asking whether to confirm or deny the uninstall process for the program. Confirm the process and wait for the uninstall process to finish. Restart your computer after the program has been uninstalled from your computer.

   

4. After restarting your computer, reinstall the program that was giving the error.
5. You can fix the error you are expericing with this method. If the dll error is continuing in spite of the solution methods you are using, the source of the problem is the Windows operating system. In order to fix dll errors in Windows you will need to complete the 4th Method and the 5th Method in the list.

Method 4: Fixing the Mmstfx.dll Issue by Using the Windows System File Checker (scf scannow) 

1. In order to run the Command Line as an administrator, complete the following steps.

   NOTE! In this explanation, we ran the Command Line on Windows 10. If you are using one of the Windows 8.1, Windows 8, Windows 7, Windows Vista or Windows XP operating systems, you can use the same methods to run the Command Line as an administrator. Even though the pictures are taken from Windows 10, the processes are similar.

   1. First, open the Start Menu and before clicking anywhere, type "cmd" but do not press Enter.
   2. When you see the "Command Line" option among the search results, hit the "CTRL" + "SHIFT" + "ENTER" keys on your keyboard.
   3. A window will pop up asking, "Do you want to run this process?". Confirm it by clicking to "Yes" button.

   

2. Paste the command in the line below into the Command Line that opens up and press Enter key.

   sfc /scannow

   

3. The scan and repair process can take some time depending on your hardware and amount of system errors. Wait for the process to complete. After the repair process finishes, try running the program that is giving you're the error.

Method 5: Fixing the Mmstfx.dll Error by Updating Windows 

Some programs require updated dynamic link libraries from the operating system. If your operating system is not updated, this requirement is not met and you will receive dll errors. Because of this, updating your operating system may solve the dll errors you are experiencing.

Most of the time, operating systems are automatically updated. However, in some situations, the automatic updates may not work. For situations like this, you may need to check for updates manually.

For every Windows version, the process of manually checking for updates is different. Because of this, we prepared a special guide for each Windows version. You can get our guides to manually check for updates based on the Windows version you use through the links below.

Guides to Manually Update the Windows Operating System 

1. Guide to Manually Update Windows 10
2. Guide to Manually Update Windows 8.1 and Windows 8
3. Guide to Manually Update Windows 7 and Windows Vista
4. Guide to Manually Update Windows XP