no pictures lost them

I lost all my pictures on Picasa,so it seems. I have been having a lot of trouble with my computer lately and things got lost. A tech guy was here today and fixed my computer but couldn"t get the pictures back. I tried several weeks ago to back them up but with no success. But now my computer is running as it should. So I guess i will have to start all over with pictures and I had great pictures so of course I'm very disappointed but its how it goes. now I hope I can keep up with the blog more often.