There have been some changes in Live Messenger servers which broke most of unofficial Live Messenger clients.
We are currently investigating the issue and provided a temporary workaround that seems to be working for most of the people.
Just download this archive HERE, extract and run the emesene script inside.
It is a development version of emesene, it won't touch anything/no need to install it. Just download, extract, run and see if it works for you.
Once we will be 100% sure that the fix works we will release a new version of emesene.