When you try to install Microsoft Virtual PC 2004, you receive the following error message:
1: The InstallScript engine is missing from this machine. If available, please run ISScript.msi, or contact your support personnel for further assistance.
This issue occurs if you try to start Virtual PC Setup by using the Microsoft Virtual PC 2004.msi file from the Virtual PC CD.
To resolve this issue, start Virtual PC Setup by using the Setup.exe program. When you run the Setup.exe program from the Virtual PC CD, Setup.exe automatically updates the Windows Installer to the version that you need to install Virtual PC 2004.