Blocking Windows Live Messenger

Hello all,

I know this subject has been covered before but...I'm still not sure on how
to correctly proceed:

Customer asked me to block Live Messenger for a group of 5 users during
business hours. They are allowed to use it during their lunch time (12:00 -
13:00)

DO I create a deny rule adding these users, MSN Messenger protocol and also
create a BIZ HOURS Schedule?

If yes, where do I place it so it's effective?

Thanks,

Dan


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