Scheduled Scan as Administrator

I notice that if I do a manual scan and click the Scan as Administrator button, many more files get successfully scanned and there are fewer errors listed in the log. Without doing this, I especially notice that my .eml files are not getting scanned. I have a nightly scan scheduled, but I have no option to scan as administrator. Why is that not an option? My user is an administrator, but I know how that is on Windows 7. Only the inactive Administrator user is a real Administrator...and I appreciate that additional layer of protection that was missing in XP. But I would like to scan all of my files...as many as possible. Many of the errors listed in the log under my user listed password errors on files, whereas the Administrative Scan doesn't appear to have trouble with that. Am I worrying needlessly? Thanks for responding.

 

Basically the System account should have access to all files. If it's not so, just grant it access to files/folders that were not scanned.