Windows XP and IE6.0 dial up problemes

[22jeff22]

I have problems with win xp that has IE6.0 and have dial -up accounts. I have several people in my town that when they try to connect they might connect at 1.2kbps sometimes higher and sometimes lower or not at all. The phone lines have been checked and the ISP said they are not having any problems. They are all using USR5610B 56K V.92 modems and are using Mcafee virusscan6.0. I have checked all the settings and everything is good. The only thing I can think of is win xp updated itself and there is a conflict with something. Any help would be greatly appreciated.

Thanks
22jeff22