Method 1: Fixing the DLL Error by Copying the Cdrpsi91.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 "Cdrpsi91.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 "Cdrpsi91.dll" library and paste it into the "C:\Windows\System32" directory.

   

6. If your system is 64 Bit, copy the "Cdrpsi91.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 "Cdrpsi91.dll" library.

   

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. Let's copy the command below and paste it in the Command Line that comes up, then let's press Enter. This command deletes the Cdrpsi91.dll library's problematic registry in the Windows Registry Editor (The library that we copied to the System32 directory does not perform any action with the library, it just deletes the registry in the Windows Registry Editor. The library that we pasted into the System32 directory will not be damaged).

   %windir%\System32\regsvr32.exe /u Cdrpsi91.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 Cdrpsi91.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 Cdrpsi91.dll

   

10. 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 Cdrpsi91.dll

    

11. 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 Cdrpsi91.dll library that we deleted.

    %windir%\SysWoW64\regsvr32.exe /i Cdrpsi91.dll

    

12. 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 Cdrpsi91.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 Cdrpsi91.dll Library to the Program Installation Directory 

1. First, you need to find the installation directory for the program you are receiving the "Cdrpsi91.dll not found", "Cdrpsi91.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 Cdrpsi91.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 Cdrpsi91.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. 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. After restarting your computer, reinstall the program that was giving the error.
5. This method may provide the solution to the dll error you're experiencing. If the dll error is continuing, the problem is most likely deriving from the Windows operating system. In order to fix dll errors deriving from the Windows operating system, complete the 4th Method and the 5th Method.

Method 4: Fixing the Cdrpsi91.dll Error using the Windows System File Checker (sfc /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 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: Fixing the Cdrpsi91.dll Errors by Manually 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.

Explanations on Updating Windows Manually 

1. Explanation on Updating Windows 10 Manually
2. Explanation on Updating Windows 8.1 and Windows 8 Manually
3. Explanation on Updating Windows 7 and Windows Vista Manually
4. Explanation on Updating Windows XP Manually