Ahh.......... this is getting very interesting.
Not only am I experiencing the problems highlighted above, in the fourth entry to this thread, but like maggioneato have been fumbling around for the first time looking for my XP firewall, to no avail.
News from amanoffewwords regarding a possible compatability problem with AOL is a first with me, but a quick run around the web would seem to suggest that there is something in this.
Yes, I am aware that the Windows Messenger Service is not associated with Windows Messenger, MSN Messenger, or such instant messaging services. Any debate on the subject really needs to emphasise this point. Confusion is rife, if understandable; extending to the AOL HelpLine tonight (a real pickle of conflicting information. .....and very cagey about the AOL/XP firewall issue). Disabling Windows Messenger Service WILL stop the Messenger pop-up spam (and, AOL HelpLine, you will still be able to instant message) BUT there are side effects as mentioned in my original entry to this thread.
My confidence in the Norton firewall is the reason why, until now, that I haven't gone looking for it's (I suspect inferior) XP equivalent. But if AOL is having problems with the XP firewall is it possible that it is compromising the ability of my Norton (updated and "security checked") to combat this particular pop-up menace. .....??? Several friends using an identical AOL/Norton combination are having similar problems, whilst those on a different ISP/Norton are not.