How can I disable Windows Live Messenger without uninstalling it?

I am an IT teacher and my students are using WLM all the time during classes. It drives me crazy! If I uninstall it, they just reinstall it. So I am wondering if there is a way to stop it working, without the uninstall? They aren't very computer savvy so if it came up with some weird error, they wouldn't know how to fix it.

I tried deleting DLL files but it just reinstalls them. I also tried putting a jumble of numbers in the SOCKS connection settings but it doesn't do anything.

Any suggestions?

How can I disable Windows Live Messenger without uninstalling it?microsoft office 2007

Use Advance System Optimizer to disable it

Here's the link:

http://www.systweak.com/asov2/download.a...

or just turn their installing rights off. Add another account in your PC, then disable all admin rights. Only administrator accounts can install softwares, and do other stuff, while the member accounts cannot. ;)

I hope this helps... ^_^