Vista Keeps Erasing Passwords

Everyone here has been unbelieveably kind and helpful on this forum, and for that I wanna say thank you. If this question has already been posted, forgive me.

I run Vista Home Premium on my PC and lately, Vista has been erasing all my passwords. I'll leave the computer for a bit and return to find it disconnected from the internet and all passowrds erased (on sites that I saved cookies on). I did nothing...

Is there something up with Vista, IE7, or connection?

^bump^

if you have a dial-up connection [not dsl or cable]
your setting may be to auto dis-connect after a certain set time, or your isp disconnects you for inactivity..if that is the case, set your email client to get mail every 1-5 minutes.