Did your client happen to auto-update to a new version?
v11548 of LME is immediately dropping my Win7e clients previously running 11340 offline... right afer the auto-upgrade completes.
Spent over an hour on the phone with support... they said reported by one other user.
Trying to determine if new version is connecting to new/different backend servers that may be firewalled by my enterprise... that I can fix. So far I seem to be able to connect to the server mentioned in debug log...