My uncle is trying to install the MindJet MindManager Viewer 7 but get's the following error message :
MindJet MindManager Viewer 7 Installer Inform...
Error 1931. The Windows Installer service cannot update the system file C:\WINDOWS\system32\msxml6r.dll because the file is protected by Windows. You may need to update your operating system for this program to work correctly.
His Windows XP SP3 system is up to date, by the way.
Any ideas as to why this is happening?