secure website problem

After a friend installed Verizon DSL on his WinXP system, it seemed to work fine for a day. After that, he was not able to get secure IE websites, such as banking & stock, to display. Later, we learned that Hotmail login, Windows Update, Symantec’s LiveUpdate and online program installs such as IE Service Pack would not work. Checks of virtually everything in IE’s Internet Properties tabs did not show any differences from a working system’s settings.

His old dial-up connection now has the same problem connecting to those sites. It had no trouble before.

Downloading programs from Download.com works fine.

Does anyone have a solution for this problem?