Test the modem, microsoft have a trouble shooting guide here:
http://www.microsoft.com/resources/d...est_modem.mspx
Take details of a another ISP with you, PM me if you want details of some that you don't need to register for. This will let you get round any problems with Freeserve ID/ Password / expired accounts so you can get on line to Freeserve to fix the account if that is the problem.
Take a spare modem with you