Start menu search function asking for password

When I do a search for a file I get asked for a password. It only accepts the password I use to sign into my administer account. (I have no other accounts). When I put the password in, it searches and searches and gives no results. When I search again the password request pops up, this time I just click on cancel and the search gives results.

I don't use this function very often so I don't know when this issue began. Any ideas how to fix this problem. I also noticed that when I click on password when requested, and the search has started, it will not stop.

XP SP2 Home Edition

 

Yes I don't usually put the last * Having a grey moment I guess.

I had a backup file in my documents. One of those put on C drive and then burned to disk. I forgot about it. I deleted it and all is fine again. Odd that you can't have a backup file on C drive without affecting search.