There are quite a few guides on how to disable this viral little program. Sadly blocking it’s default port rarely works, because doing so causes the program to switch to port 80, which for most would mean blocking http traffic too.
Several ways to do this on the internet involve editing the registry, this is something that doesn’t appear to work any more.
The only way I’ve found that works is to edit the computers group policy (start > run > gpedit.msc). Under Administrative Templates and Windows components, you’ll find Windows Messenger. Simply set “Do not allow windows messenger to be run” to enabled.
Thats it.
Update: This doesn’t work for Live Messenger, one method I have found that uninstalls WLM completely is to run a command prompt (as administrator), and simply type: msiexec /x {B1403D7D-C725-4858-AACC-7E5FA2D72859}.
After quite extensive testing I still haven’t yet managed to successfully un-install windows live messenger, other then stripping it out completely with a custom windows build – but that just isn’t practical for the solution I need.
One really does have to wonder why Microsoft don’t allow this feature.