I have Windows 7 Home Premium, and would like to do some maintenance tasks such as running Disk Defragmenter. However, this and other programs and applications that I'm accustomed to using are now blocked.

For these programs, there is a shield icon next to their icons and nothing happens when I click on them. I notice that the screen blinks slightly, but I do not get prompted for a password and the program still does not run. It seems these programs may only be accessible through an Administrator account. However, right-clicking and selecting "Run As Administrator" does not work.

After some research, I found a way to enable the hidden built-in Administrator account.

• I booted the computer into safe mode.
• In the command prompt, I typed net user administrator /active:yes.
• I gave the account a password.
• I rebooted the system.

There is now an Administrator account on the home screen. However, the locked programs behave no differently for me when I use this account.

What could cause this problem? How can I fix it?