Don't overwrite a PST file. Just configure Outlook to use your old one.
Take a look at these pages for info on Outlook data backup: http://www.slipstick.com/config/backup.htm
Want to reply to this thread or ask your own question?
You'll need to choose a username for the site, which only take a couple of moments. After that, you can post your question and our members will help you out.