The database engine has times out

I cant open my company in sage and its driving me insane!

When the window pops up to open your company - I have everything backed up on a memory stick, and when I open the folders I have created (Feb 2010, March 2010), the back up is not there. However if I go into my computer and look at what is on the stick, I can see everything.

Why can I not see it in sage???