When you attempt to install a Windows Installer package (.MSI) on a Windows Server 2003 domain controller, you receive:
This installation package could not be opened. Verify that the package exists and that you can access it, or contact the application vendor to verify that this is a valid Windows Installer package.
You will experience this behavior if the installation files are located in the Sysvol folder.
The Windows Server 2003 Sysvol folder is created with the SHI1005_FLAGS_RESTRICT_EXCLUSIVE_OPENS attribute, which prevents it from being exclusively locked and causing Active Directory directory service synchronization problems.
DO NOT use the Sysvol folder as a Windows Installer installation point.