Okay, not holding out much hope here, but in case one of my Many Readers is, in fact, an expert in this area …
I’m part of a pilot Windows Messenger (IM via Exchange) group in my company, and, after about a year of the service working just fine for me, I came to realize that my WM was not working correctly.
Testing on another person’s machine demonstrated it wasn’t my account configuration; I can sign in elsewhere with nary a problem.
On my machine, though, it appears that the WM client polls the Exchange server up front just fine, to get the current contact status. After that, though, it never polls the server. I can send IMs just fine, but nobody can send them back to me (sometimes they get an error saying I’m not signed in, sometimes not), and my contact list never gets its status updated.
At our internal IT folks’ behest, I’ve uninstalled WM as much as possible — it’s a Windows component, so the most you can theoretically do is uncheck the box to keep it from starting; I’ve also found an uninstall script (running rundll32 against the original inf package for the previous version, which I’ve run), and I’ve zapped the directory and the Registry keys I recognize for it, and downloaded the latest-greatest (5.0). That version, though, still thinks the system is there; it gives me just a Repair option.
At any rate, still no go.
I am not using a proxy, I am not behind a firewall, and everything should be right as rain. The alternatives I’m being given are either (a) rebuild the machine from scratch, or (b) don’t use WM. If it comes to that, I’ll go with (b), but if anyone has additional ideas, I’m open to them.
UPDATE: I’m pinging the folks on this MS support board, so we’ll see if they have any answers.