The legitimate isarcextract.dll is not a virus. However, malware sometimes uses the same name. Always check the digital signature of the file. Right-click the DLL > Properties > Digital Signatures. A valid signature should indicate the publisher as "Jordan Russell" or related to Inno Setup.
# Example PowerShell command (run as admin) Copy-Item -Path "C:\Downloads\isarcextract.dll" -Destination "C:\Windows\System32" -Force install isarcextract.dll
If you later need to remove the DLL:
No official Microsoft or Windows system process uses this file. It is a third-party component. Therefore, downloading it from random “DLL download” websites is a high-risk activity . We will focus on safe methods. The legitimate isarcextract