Method 1: Fixing the DLL Error by Copying the Mpoai9.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 "Mpoai9.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 "Mpoai9.dll" library and paste it into the "C:\Windows\System32" directory.

   

3. If you are using a 64 Bit operating system, copy the "Mpoai9.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 "Mpoai9.dll" library into both directories.

   

4. First, we must run the Windows Command Prompt as an administrator.

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

   1. Open the Start Menu and type in "cmd", but don't press Enter. Doing this, you will have run a search of your computer through the Start Menu. In other words, typing in "cmd" we did a search for the Command Prompt.
   2. When you see the "Command Prompt" option among the search results, push the "CTRL" + "SHIFT" + "ENTER
   " keys on your keyboard.
   3. A verification window will pop up asking, "Do you want to run the Command Prompt as with administrative permission?" Approve this action by saying, "Yes".

   

5. 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 Mpoai9.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 Mpoai9.dll

   

6. If you are using a 64 Bit operating system, after doing the commands above, you also need to run the command below. With this command, we will also delete the Mpoai9.dll library's damaged registry for 64 Bit (The deleting process will be only for the registries in Regedit. In other words, the dll file you pasted into the SysWoW64 folder will not be damaged at all).

   %windir%\SysWoW64\regsvr32.exe /u Mpoai9.dll

   

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

   %windir%\System32\regsvr32.exe /i Mpoai9.dll

   

8. 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 Mpoai9.dll library that we deleted.

   %windir%\SysWoW64\regsvr32.exe /i Mpoai9.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 Mpoai9.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 Mpoai9.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 Mpoai9.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: Uninstalling and Reinstalling the Program that Gives You the Mpoai9.dll Error 

1. Push the "Windows" + "R" keys at the same time to open the Run window. Type the command below into the Run window that opens up and hit Enter. This process 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. 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 Mpoai9.dll Error Using the Windows System File Checker 

1. First, we must run the Windows Command Prompt as an administrator.

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

   1. Open the Start Menu and type in "cmd", but don't press Enter. Doing this, you will have run a search of your computer through the Start Menu. In other words, typing in "cmd" we did a search for the Command Prompt.
   2. When you see the "Command Prompt" option among the search results, push the "CTRL" + "SHIFT" + "ENTER
   " keys on your keyboard.
   3. A verification window will pop up asking, "Do you want to run the Command Prompt as with administrative permission?" Approve this action by saying, "Yes".

   

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 Mpoai9.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.

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