Dell Dimension 3000 XP having problems while on-line with Comcast hi-speed cable connection at home. After transferring RoadRunner e-mail to Comcast.net e-mail (which did not transfer my Inbox and Addresses), I often get CANNOT FIND SERVER/THIS PAGE CANNOT BE DISPLAYED after entering username and password. Examples are Chase.com, Craigslist Account, Comcast E-mail account, etc. I can get to the Home Pages but not to my personal stuff. I may have messed up settings in "Internet Options". Any basic starting point for solving this?