If you downloaded the game via a browser, clear your browser cache and redownload the installer files entirely. A fluctuating internet connection can easily ruin high-compression archives. Frequently Asked Questions
Type the following command to check the deployment image and press Enter: DISM.exe /Online /Cleanup-image /Restorehealth isdonedll error unarcdll error7 best
Use MemTest86 or Windows Memory Diagnostic. If you downloaded the game via a browser,
If a single megabyte of a 50GB highly compressed split-archive is dropped or corrupted during download, the decompression algorithm breaks entirely at that specific block. isdonedll error unarcdll error7 best
in Windows Defender:
If all else fails, the files you are executing are likely fundamentally broken or incomplete.
Windows or your antivirus may block unarc.dll or isdone.dll from writing temporary files.