
You notice the error message because the Windows Installer service uses the SYSTEM account to install software.

The SYSTEM account does not have Full Control permissions on the folder that you are trying to install the Windows Installer package to.The drive that contains the folder that you are trying to install the Windows Installer package to is accessed as a substitute drive.


When you try to install a Windows Installer package, you may receive the following error message:Įrror 1603: A fatal error occurred during installation. This article helps fix the error 1603 that occurs when you install a Microsoft Windows Installer package.Īpplies to: Windows 10 - all editions Original KB number: 834484 Symptoms
