One other thing you could try is lower the User Account Control settings on the computer.
In the image below I have mine set one notch below 'recommended settings' and Windows may complain at first, but this has helped some people with the Administrator type errors.

Attached Files (Click to download or enlarge) (Only available when you are logged in)
UAC.jpg (135.27 KB, 46 downloads)
Control Panel-User Accounts-Change User Account Control settings

I do not work here, but the benefits are still awesome
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