The .NET Messenger Service has been unavailable for quite a while today, which resulted in automatic disconnects all over the world.
All systems seem to be problematic at the time of writing.
This is the error (81000377) I got when trying to sign in to MSN Messenger.

Checked the .NET Messenger Service status and indeed there’s problem with the .NET Messenger Service.

There’s no workaround to get connect except to wait for the service to be restored 🙁