Manage Accounts box is blank

Hello,

I have had this problem for a bit but now it is becoming an issue.

I am the Admin my Windows Vista home premium. I created 2 other accounts.
When I go to Control Panel -> User Accounts -> Manage Accounts the box where
the other accounts are supposed is blank. Anyone have an idea what is going
on and how I fix it?

One of the other accounts password no longer works and I need to fix it.
Thanks

Larry C