In this post, we will break down why this happens and provide the ultimate fix for the "ISDone.dll Unarc.dll" error sequence.
Force Windows to recognize the DLL files using the Command Prompt (Admin) . Run CMD as Administrator. Type regsvr32 isdone.dll and press Enter. Type regsvr32 unarc.dll and press Enter. 3. Run System File Checker (SFC) isdone.dll isarcextract unarc.dll fix download manager