Change to Administrator Account

Hi,

I am unable to search for programs and files on my computer. When I click start (on taskbar) and type something into the search engine, I get this message:

No matter what program or file I try to search for, I get this message. I am the only user account on this computer, so I should be administrator, but I'm not.

Please help me because I really need to resolve this problem!

(I also the print screen of the error message.)