It's a system protection method. If you had full rights and malware got into the system, it too could get full rights and cause all kinds of problems.

>I have tried this command. It changes the icon layout and when clicked on it, nothing happens:
>
>%windir%\system32\runas.exe /user:administrator "explorer.exe /separate"
>
>This has been discussed at this page:
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>http://superuser.com/questions/327907/opening-explorer-shell-with-admin-privileges-on-xp-with-ie7-installed
>
>This is becoming to be highly frustrated. You work on the C: drive with full administrative privileges with no access to modify anything on the disk.