God, get msn messenger 8.5. If you don't have that it's a good idea anyways. The older ones are easier for hackers to gain access into your computer with. To put msn messenger into your "allowed" list, go to the control panel, switch to classic view, and then double click windows firewall. Go to the exceptions tab and see that "windows live messenger" is checked. If it's not, check it. If it's not in the list, you'll have to click "add program" and go into the program files and find the original exe that msn messenger comes with. very simple...that is, if you don't have another firewall...