Also I remember a related error message that you may get specific to OffCAT installation. "The Installed has insufficient privileges to access this directory "C:\program files\Microsoft\OffCAT". The installation cannot continue. Log on as administrator or contact your system administrator".
If you attempt to install OffCAT as a non-administrative user, you will receive the following error during OffCAT setup. In such scenario to install the Office Configuration Analyzer Tool (OffCAT), please make sure that you log into your computer as a member of the local Administrators group.