Popup blocking interfering?

[KimO]

A few days ago my computer told me it had installed a new
popup blocker from Microsoft, which was fine with me. My
e-mail seemed to work just fine until today. Sometime
yesterday, I got a notice that McAfee had updated my
VirusScan. Today, I started getting a VirusScan dialog
that e-mails I was sending had not been sent because of
a "Protocol Error," even though they did show up in
my "Sent" file, and I did not get a
return "undeliverable" message. I went online to chat
with McAfee's tech support, and they couldn't find any
problem with their part of the system. Test e-mails sent
to myself with VirusScan and Personal Firewall Plus both
disabled did come back undeliverable.

I find it coincidental that this only started happening
after the new update of VirusScan (when McAfee can find
nothing wrong with that update) and a few days after the
installation of the new MS popup blocker.

Has anyone else experienced a conflict with this new
setup? The VirusScan dialog showing "Protocol Error"
only started after the latest update of VirusScan.
McAfee told me I need to contact my "system provider."

HELP?!?!?