This is popular question. You may have two options. Check this post.
Vista doesn't remember mapped drives
4 posts - Last post: Mar 27, 2008
What if Windows logon Credential is greyed out beacuse it's Vista Home
Premium? At least that's the only reason I can think it's greyed out. ...
Bob Lin, Microsoft-MVP, MCSE & CNE
Networking, Internet, Routing, VPN Troubleshooting on
How to Setup Windows, Network, VPN & Remote Access on
"Tom Newton" <firstname.lastname@example.org> wrote in message
> Is there a way to make Vista Home Premium remember network passwords so I
> not have to re-enter them every time I re-start my computer. I have tried
> checking the remember password option but it does not do anything.
> Simply want to maintain a network connection to 2 computers and a shared
> printer on a home network. Please don't tell me that Vista Home Premium
> doesn't remember network passwords and Vista Business and Ultimate do!
> Please tell me there is a fix