A deny permission was assigned on the root directory by right clicking on C:\ then using security tab. The deny permission was set on Authenticated Users and One Guest User.
The objective was to deny all access from this Guest User to all files and folders. However the result was deny of access to all users including administrators.
To fix this I've booted the computer in Safemode with command prompt and managed to enable the default administrator account named "Administrator". Which is inactive by default. But this account doesn't have access to the root directory either.
My system is a dual operating system. With Windows XP and Windows 7 (Release Candidate version). When I log boot with Windows XP the partition on Windows 7 is not accessible.
How can I get back access to my files under the Windows 7 partition? Will reinstalling Windows 7 solve this problem?