Method 1: Installing the Df1tfilter.dll Library to the Windows System Directory 

1. The file you downloaded is a compressed file with the ".zip" extension. In order to install it, first, double-click the ".zip" file and open the file. You will see the library named "Df1tfilter.dll" in the window that opens up. This is the library you need to install. Drag this library to the desktop with your mouse's left button.

   

2. Copy the "Df1tfilter.dll" library you extracted and paste it into the "C:\Windows\System32" directory.

   

3. If your system is 64 Bit, copy the "Df1tfilter.dll" library and paste it into "C:\Windows\sysWOW64" directory.

   NOTE! On 64 Bit systems, you must copy the dynamic link library to both the "sysWOW64" and "System32" directories. In other words, both directories need the "Df1tfilter.dll" library.

   

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 Df1tfilter.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 Df1tfilter.dll

   

6. If you are using a Windows version that has 64 Bit architecture, after running the above command, you need to run the command below. With this command, we will clean the problematic Df1tfilter.dll registry for 64 Bit (The cleaning process only involves the registries in Regedit. In other words, the dynamic link library you pasted into the SysWoW64 will not be damaged).

   %windir%\SysWoW64\regsvr32.exe /u Df1tfilter.dll

   

7. We need to make a new registry for the dynamic link library in place of the one we deleted from the Windows Registry Editor. In order to do this process, copy the command below and after pasting it in the Command Line, press Enter.

   %windir%\System32\regsvr32.exe /i Df1tfilter.dll

   

8. If you are using a Windows with 64 Bit architecture, after running the previous command, you need to run the command below. By running this command, we will have created a clean registry for the Df1tfilter.dll library (We deleted the damaged registry with the previous command).

   %windir%\SysWoW64\regsvr32.exe /i Df1tfilter.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 Df1tfilter.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 Df1tfilter.dll Library Into The Program Installation Directory 

1. First, you must find the installation directory of the program (the program giving the dll error) you are going to install the dynamic link library to. In order to find this directory, "Right-Click > Properties" on the program's shortcut.

   

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

   

3. Copy the Df1tfilter.dll library into this directory that opens.

   

4. This is all there is to the process. Now, try to run the program again. If the problem still is not solved, you can try the 3rd Method.

Method 3: Doing a Clean Install of the program That Is Giving the Df1tfilter.dll Error 

1. Open the Run window by pressing the "Windows" + "R" keys on your keyboard at the same time. Type in the command below into the Run window and push Enter to run it. This command will open the "Programs and Features" window.

   appwiz.cpl

   

2. The programs listed in the Programs and Features window that opens up are the programs installed on your computer. Find the program that gives you the dll error and run the "Right-Click > Uninstall" command on this program.

   

3. Following the instructions that come up, uninstall the program from your computer and restart your computer.

   

4. After restarting your computer, reinstall the program that was giving the error.
5. This process may help the dll problem you are experiencing. If you are continuing to get the same dll error, the problem is most likely with Windows. In order to fix dll problems relating to Windows, complete the 4th Method and 5th Method.

Method 4: Fixing the Df1tfilter.dll Error Using the Windows System File Checker 

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 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 Df1tfilter.dll Errors by Updating the Windows Operating System 

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 for All Windows Versions 

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