Hi Lisa,

Don't run 2 firewalls together - they'll conflict with each other & won't work properly. If you're sure that you have a Norton firewall (Norton Anti Virus doesn't include a firewall) then turn off the Windows firewall & just configure the Norton to allow LW: PortForward.com - Free Help Setting up Your Router or Firewall

You could also try removing any current LW rules from the Norton firewall & then setting new rules: http://www.gnutellaforums.com/226610-post6.html

If LW's just started acting up after you installed Pro, delete LW's preferences folder when LW's properly closed. This thread has info about that (& a link for Vista users), plus heaps of other connection fixes to try: If LW Will Not Connect
If deleting the prefs folder doesn't work, next thing to try would be deleting/replacing the gnutella.net file Otherwise, go through all the other fixes.

If nothing helps & you're sure that you've done everything correctly, maybe there's a problem with your router. Have a look at all the boxes that connect to your computer. Your router (or modem/router) is the box that lets you connect to the net. It's got lots of little lights on it. Have a look for brand & model (if nothing's showing then have a look underneath).
If you have a wireless connection then the router might be in another room.