Processes in Microsoft 365 for setting up Office apps, redeeming product keys, and activating licenses.
Is this on a home PC or a work PC? If the latter, are you connected to it via RDC?
Check the permissions on the C:\Config.msi folder itself. What are they?
My guess is you're having UAC issues. Try starting the installation of Office by right-clicking the setup and choosing "Run as Administrator". Having administrator rights and using the actual "Administrator" account in Vista are different, it seems.
Brian Tillman [MVP-Outlook]
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