Is there a reason you can't run the current version of msn messenger/windows live?
I'm using Avast love it and I have windows live/messenger installed, actually just put on the newest version last night. I'm using Win 7 64 bit. I'll admit I did have issues with one of the older versions of msn though so perhaps an update of that will resolve.
Just my $0.02 though.
It may have been also that you had the firewall in Avast set to block the port msn was trying to use to connect.
I love Avast it was great that it blocked many viruses but I don't like that there are missing features on latest WLM. My computer is new and is a month old. I installed latest WLM when i got the computer. I disabled firewall in Avast. So how do I fix this? And also what do you mean "an update"