What are you running for an operating system? Windows XP? If so, check to see if you have Service Pack 2 installed (right-click, properties on My Computer - should say so on front panel). Another way to check and see if you have holes in your computer is to run the Services management console (Start, Run, services.msc). Look for the Messenger service, and make sure it says "Disabled" under Startup Type. (It's not the same thing as MSN Messenger or Windows Messenger.)