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

1. The file you will download is a compressed file with the ".zip" extension. You cannot directly install the ".zip" file. Because of this, first, double-click this file and open the file. You will see the file named "Acsui.dll" in the window that opens. Drag this file to the desktop with the left mouse button. This is the file you need.

   

2. Copy the "Acsui.dll" file file you extracted.
3. Paste the dll file you copied into the "C:\Windows\System32" folder.

   

4. If you are using a 64 Bit operating system, copy the "Acsui.dll" file and paste it into the "C:\Windows\sysWOW64" as well.

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

   

5. 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.

   

6. 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 Acsui.dll file's problematic registry in the Windows Registry Editor (The file that we copied to the System32 folder does not perform any action with the file, it just deletes the registry in the Windows Registry Editor. The file that we pasted into the System32 folder will not be damaged).

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

   

7. 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 Acsui.dll registry for 64 Bit (The cleaning process only involves the registries in Regedit. In other words, the dll file you pasted into the SysWoW64 will not be damaged).

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

   

8. 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 Acsui.dll

   

9. 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 Acsui.dll file (We deleted the damaged registry with the previous command).

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

   

10. 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 Acsui.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 Acsui.dll File to the Software File Folder 

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

   

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

   

3. Copy the Acsui.dll file into the folder we opened.

   

4. The installation is complete. Run the software that is giving you the error. If the error is continuing, you may benefit from trying the 3rd Method as an alternative.

Method 3: Uninstalling and Reinstalling the Software that Gives You the Acsui.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. On the Programs and Features screen that will come up, you will see the list of softwares on your computer. Find the software 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 software?" confirmation window. Confirm the process and wait for the software 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 software. After the software is uninstalled, restart your computer.

   

4. 4. After restarting your computer, reinstall the software that was giving you the error.
5. You may be able to solve the dll error you are experiencing by using this method. If the error messages are continuing despite all these processes, we may have a problem deriving from Windows. To solve dll errors deriving from Windows, you need to complete the 4th Method and the 5th Method in the list.

Method 4: Solving the Acsui.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 in the line below into the Command Line that opens up and press Enter key.

   sfc /scannow

   

3. The scan and repair process can take some time depending on your hardware and amount of system errors. Wait for the process to complete. After the repair process finishes, try running the software that is giving you're the error.

Method 5: Solving the Acsui.dll Error by Updating Windows 

Some softwares require updated dll files 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 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