Microsoft Windows Live Messenger version 2009 build 14.0.8064.XXX suffers from a crash / denial of service vulnerability when a charset is changed to something that does not exist during conversation.
You can download this advisory from the following link: https://packetstormsecurity.com/files/download/75041/wlm-dos.txt
Source: https://packetstormsecurity.com/files/75041/Windows-Live-Messenger-Denial-Of-Service.html