There’s been Messenger server problems today, causing instant messages not to be delivered to contacts and possibly issues with signing in.
This is most likely due to changes being made for tomorrow’s (Sept. 15th) forced upgrade to Windows Live Messenger 2009. I would expect it to be resolved by tomorrow.
If you’re not aware of the forced upgrade, as of tomorrow if you’re using Windows Live Messenger 8.x, you will be forced to update to the 2009 version to sign in to Messenger. This is due to a security issue found in the Microsoft’s ATL library, which is only fixed in the latest version of Messenger. The MessengerSays blog has the full announcement. As well, this forced upgrade has already been shaky, with workarounds required for some versions of Windows which aren’t officially “supported”. You can upgrade Messenger at the Windows Live download site, or install the MSI files yourself here on my blog. Continue at Messenger team blog