Method 1: Copying the Lfeps12n.dll Library to the Windows System Directory 

1. The file you downloaded is a compressed file with the extension ".zip". This file cannot be installed. To be able to install it, first you need to extract the dynamic link library from within it. So, first double-click the file with the ".zip" extension and open the file.
2. You will see the library named "Lfeps12n.dll" in the window that opens. This is the library you need to install. Click on the dynamic link library with the left button of the mouse. By doing this, you select the library.

   

3. Click on the "Extract To" button, which is marked in the picture. In order to do this, you will need the Winrar program. If you don't have the program, it can be found doing a quick search on the Internet and you can download it (The Winrar program is free).
4. After clicking the "Extract to" button, a window where you can choose the location you want will open. Choose the "Desktop" location in this window and extract the dynamic link library to the desktop by clicking the "Ok" button.

   

5. Copy the "Lfeps12n.dll" library file you extracted.
6. Paste the dynamic link library you copied into the "C:\Windows\System32" directory.

   

7. If your system is 64 Bit, copy the "Lfeps12n.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 "Lfeps12n.dll" library.

   

8. 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.

   

9. Paste the command below into the Command Line that will open up and hit Enter. This command will delete the damaged registry of the Lfeps12n.dll library (It will not delete the file we pasted into the System32 directory; it will delete the registry in Regedit. The file we pasted into the System32 directory will not be damaged).

   %windir%\System32\regsvr32.exe /u Lfeps12n.dll

   

10. 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 Lfeps12n.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 Lfeps12n.dll

    

11. 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 Lfeps12n.dll

    

12. If you are using a 64 Bit operating system, after running the command above, you also need to run the command below. With this command, we will have added a new library in place of the damaged Lfeps12n.dll library that we deleted.

    %windir%\SysWoW64\regsvr32.exe /i Lfeps12n.dll

    

13. You may see certain error messages when running the commands from the command line. These errors will not prevent the installation of the Lfeps12n.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 Lfeps12n.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 "Lfeps12n.dll is missing", "Lfeps12n.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 Lfeps12n.dll library into the directory we opened up.

   

4. That's all there is to the installation process. Run the program giving the dll error again. If the dll error is still continuing, completing the 3rd Method may help fix your issue.

Method 3: Uninstalling and Reinstalling the Program That Is Giving the Lfeps12n.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. On the Programs and Features screen that will come up, you will see the list of programs on your computer. Find the program that gives you the dll error and with your mouse right-click it. The right-click menu will open. Click the "Uninstall" option in this menu to start the uninstall process.

   

3. You will see a "Do you want to uninstall this program?" confirmation window. Confirm the process and wait for the program to be completely uninstalled. The uninstall process can take some time. This time will change according to your computer's performance and the size of the program. After the program is uninstalled, restart your computer.

   

4. 4. After restarting your computer, reinstall the program that was giving you 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 Lfeps12n.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 Lfeps12n.dll Errors by Updating the Windows Operating System 

Most of the time, programs have been programmed to use the most recent dynamic link libraries. If your operating system is not updated, these files cannot be provided and dll errors appear. So, we will try to fix the dll errors by updating the operating system.

Since the methods to update Windows versions are different from each other, we found it appropriate to prepare a separate article for each Windows version. You can get our update article that relates to your operating system version by using 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