Method 1: Copying the Bestfixexp.dll File to the Windows System Folder 

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 dll file from within it. So, first double-click the file with the ".zip" extension and open the file.
2. You will see the file named "Bestfixexp.dll" in the window that opens. This is the file you need to install. Click on the dll file with the left button of the mouse. By doing this, you select the file.

   

3. Click on the "Extract To" button, which is marked in the picture. In order to do this, you will need the Winrar software. If you don't have the software, it can be found doing a quick search on the Internet and you can download it (The Winrar software 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 dll file to the desktop by clicking the "Ok" button.

   

5. Copy the "Bestfixexp.dll" file you extracted and paste it into the "C:\Windows\System32" folder.

   

6. If your operating system has a 64 Bit architecture, copy the "Bestfixexp.dll" file and paste it also into the "C:\Windows\sysWOW64" folder.

   NOTE! On 64 Bit systems, the dll file must be in both the "sysWOW64" folder as well as the "System32" folder. In other words, you must copy the "Bestfixexp.dll" file into both folders.

   

7. 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.

   

8. Paste the command below into the Command Line window that opens and hit the Enter key on your keyboard. This command will delete the Bestfixexp.dll file's damaged registry (It will not delete the file you pasted into the System32 folder, but will delete the registry in Regedit. The file you pasted in the System32 folder will not be damaged in any way).

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

   

9. 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 Bestfixexp.dll file from the 64 Bit architecture (The Cleaning process is only with registries in the Windows Registry Editor. In other words, the dll file that we pasted into the SysWoW64 folder will stay as it is).

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

   

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

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

    

11. 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 Bestfixexp.dll file (We deleted the damaged registry with the previous command).

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

    

12. If you did the processes in full, the installation should have finished successfully. If you received an error from the command line, you don't need to be anxious. Even if the Bestfixexp.dll file was installed successfully, you can still receive error messages like these due to some incompatibilities. In order to test whether your dll problem was solved or not, try running the software giving the error message again. If the error is continuing, try the 2nd Method to solve this problem.

Method 2: Copying The Bestfixexp.dll File Into The Software File Folder 

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

   

2. Open the software's file folder by clicking on the Open File Location button in the Properties window that comes up.

   

3. Copy the Bestfixexp.dll file into the folder we opened up.

   

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

Method 3: Uninstalling and Reinstalling the Software That Is Giving the Bestfixexp.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 screen will come up. You can see all the softwares installed on your computer in the list on this screen. Find the software 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 software. Confirm the process and wait for the uninstall process to finish. Restart your computer after the software has been uninstalled from your computer.

   

4. 4. After restarting your computer, reinstall the software that was giving you 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: Solving the Bestfixexp.dll error with 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. After typing the command below into the Command Line, push Enter.

   sfc /scannow

   

3. Depending on your computer's performance and the amount of errors on your system, this process can take some time. You can see the progress on the Command Line. Wait for this process to end. After the scan and repair processes are finished, try running the software giving you errors again.

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

Most of the time, softwares have been programmed to use the most recent dll files. If your operating system is not updated, these files cannot be provided and dll errors appear. So, we will try to solve 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 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