Problems receiving email - intermittent

Is anyone else having occasional trouble receiving emails? I never know I haven't received one until I email a client for the 3rd time and finally I get one back that says "I've responded to this 3 times". I thought it could be my service provider, COX, but they were about as helpful as a worm trying to push a large boulder......so I am thinking it is Vistas. Anyone?

Which program are you using for mail? Setup a gmail.com account and test with it. Did you do a mapifix? All you updates applied? Run error checking and defrag. Did you reset your router and modem?

I am running Windows Mail. I'll try setting up a Gmail account and running my other account through that. I'll try the other things also. Thanks much!