Method 1: Fixing the DLL Error by Copying the Firdecimfiltmex.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 "Firdecimfiltmex.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 "Firdecimfiltmex.dll" library file you extracted.
3. Paste the dynamic link library you copied into the "C:\Windows\System32" directory.

   

4. If you are using a 64 Bit operating system, copy the "Firdecimfiltmex.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 "Firdecimfiltmex.dll" library into both directories.

   

5. In order to complete this step, you must run the Command Prompt as administrator. In order to do this, all you have to do is follow the steps below.

   NOTE! We ran the Command Prompt using Windows 10. If you are using Windows 8.1, Windows 8, Windows 7, Windows Vista or Windows XP, you can use the same method to run the Command Prompt as administrator.

   1. Open the Start Menu and before clicking anywhere, type "cmd" on your keyboard. This process will enable you to run a search through the Start Menu. We also typed in "cmd" to bring up the Command Prompt.
   2. Right-click the "Command Prompt" search result that comes up and click the Run as administrator" option.

   

6. 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 Firdecimfiltmex.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 Firdecimfiltmex.dll

   

7. 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 Firdecimfiltmex.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 Firdecimfiltmex.dll

   

8. You must create a new registry for the dynamic link library that you deleted from the registry editor. In order to do this, copy the command below and paste it into the Command Line and hit Enter.

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

   

9. 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 Firdecimfiltmex.dll library that we deleted.

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

   

10. You may see certain error messages when running the commands from the command line. These errors will not prevent the installation of the Firdecimfiltmex.dll library. In other words, the installation will finish, but it may give some errors because of certain incompatibilities. After restarting your computer, to see if the installation was successful or not, try running the program that was giving the dll error again. If you continue to get the errors when running the program after the installation, you can try the 2nd Method as an alternative.

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

1. In order to install the dynamic link library, you need to find the installation directory for the program that was giving you errors such as "Firdecimfiltmex.dll is missing", "Firdecimfiltmex.dll not found" or similar error messages. In order to do that, Right-click the program's shortcut and click the Properties item in the right-click menu that appears.

   

2. Click on the Open File Location button that is found in the Properties window that opens up and choose the folder where the application is installed.

   

3. Copy the Firdecimfiltmex.dll library.
4. Paste the dynamic link library you copied into the program's installation directory that we just opened.

   

5. When the dynamic link library is moved to the program installation directory, it means that the process is completed. Check to see if the issue was fixed by running the program giving the error message again. If you are still receiving the error message, you can complete the 3rd Method as an alternative.

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

1. Open the Run tool by pushing the "Windows" + "R" keys found on your keyboard. Type the command below into the "Open" field of the Run window that opens up and press Enter. This command will open the "Programs and Features" tool.

   appwiz.cpl

   

2. The Programs and Features window will open up. Find the program that is giving you the dll error in this window that lists all the programs on your computer and "Right-Click > Uninstall" on this program.

   

3. Uninstall the program from your computer by following the steps that come up and restart your computer.

   

4. After restarting your computer, reinstall the program that was giving the error.
5. You may be able to fix the dll error you are experiencing by using this method. If the error messages are continuing despite all these processes, we may have a issue deriving from Windows. To fix dll errors deriving from Windows, you need to complete the 4th Method and the 5th Method in the list.

Method 4: Fixing the Firdecimfiltmex.dll Error using the Windows System File Checker (sfc /scannow) 

1. In order to complete this step, you must run the Command Prompt as administrator. In order to do this, all you have to do is follow the steps below.

   NOTE! We ran the Command Prompt using Windows 10. If you are using Windows 8.1, Windows 8, Windows 7, Windows Vista or Windows XP, you can use the same method to run the Command Prompt as administrator.

   1. Open the Start Menu and before clicking anywhere, type "cmd" on your keyboard. This process will enable you to run a search through the Start Menu. We also typed in "cmd" to bring up the Command Prompt.
   2. Right-click the "Command Prompt" search result that comes up and click the Run as administrator" option.

   

2. Paste the command below into the Command Line that opens up and hit the Enter key.

   sfc /scannow

   

3. This process can take some time. You can follow its progress from the screen. Wait for it to finish and after it is finished try to run the program that was giving the dll error again.

Method 5: Getting Rid of Firdecimfiltmex.dll Errors by Updating the Windows Operating System 

Some programs need updated dynamic link libraries. When your operating system is not updated, it cannot fulfill this need. In some situations, updating your operating system can solve the dll errors you are experiencing.

In order to check the update status of your operating system and, if available, to install the latest update packs, we need to begin this process manually.

Depending on which Windows version you use, manual update processes are different. Because of this, we have prepared a special article for each Windows version. You can get our articles relating to the manual update of the Windows version you use from the links below.

Windows Update Guides 

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