The ‘Unarc.dll returned an error‘ in Windows is usually triggered when faulty Unarc.dll file is stored on your Windows. This error prevents you from installing games or applications. This error is also found when the installation files are corrupted.

1. Clean all Temporary System Files
It is very important to have enough storage before installing an app. If the setup cannot write temporary files, you will not be able to continue with the installation process. To create space, you usually cannot delete your files and folders as they are important. However, you should try to delete the temporary files. Follow the steps below to create space by deleting temporary files.
- press the Windows key + R to open the Run program.
- Now write Temperature and press the Ok option.
run temporary command - select All the files and press the button Shift + Delete button. then select Yes to confirm.
Delete all temporary files - Again, open run program pressing Windows key + R from the keyboard
- Write %temperature% and press the Enter key.
Delete temporary folders, documents and files permanently - Now select all files and press the button shift key + delete button. So click on Yes allow.
Delete all local temporary files - press the Windows key + R, write prefetchand click OK.
- Press Continue to access the folder, and then select All the files. press the Shift + Delete key and click Yes allow.
Delete all prefetch files - Now open the File Browser Y the right button of the mouse about him network option in the left pane.
- select properties and then click Internet option.
- Click on settings from the General tab. Then press the button “View file” option.
Clear network file cache - select All the filespress the Shift + Delete key, and permanently delete all these temporary files. Press OK.
delete network cache - Now reboot your system and check if the error appears or not.
2. Download the missing DLL file
The following DLL error appears mainly if the unarc.dll file is missing from your system. In this case, you can download the file from the Internet. Follow these steps to download the missing DLL file.
- Go to dll files. Then scroll down to the bottom of the page and press the button Discharge.
Download Unarc.dll zip file to fix Unarc.dll returned an error code on Windows - When the zip file is downloaded on your system, extract it with the help of any extraction tool like WinRAR.
- Now place the unarc.dll file in the directory that applies to your PC, such as;
C:\Windows\System32 (on a 32-bit computer) C:\Windows\SysWOW64 (on a 64-bit computer)
- Now restart your computer and try to download the game again. Now check if the error is resolved.
5. Use the Regsvr32 tool to re-register the Unarc.dll file
If you still get the Unarc.dll returned error code in Windows, you can re-register the .dll file on your system. Sometimes the .dll file stored in your system is corrupted that’s why you should try to re-register the dll file. Follow these steps:
- Click on the Start Menu and search shell power.
- Click on Execute as an administrator. Now type the following command;
Run PowerShell as administrator
For the System32 folder on 32-bit operating systems
regsvr32 %systemroot%\System32\unarc.dll
For SysWOW64 operating system; then type the following command
regsvr32 %systemroot%\SysWOW64\unarc.dll

- Once the process is complete, a registration message will appear. Now try to install the game again and check if it installs without issue.