No connection

I too have a connection problem, but with Kazaa. I've been using v2.1.0 k++ Edition {build 2} for about 12 months. I formatted my hdd and reinstalled an even older version of Kazaa that wouldn't connect. I uninstalled it, removed any registry files it left behind and reinstalled v2.1. It starts, and says connecting, but never does. Since the format, I've installled ZAP v5 and changed my antivirus to McAfee. I've tried shutting down both programs and connecting to Kazaa, but with the same result. A tech friend told me that some ISP's will block certain P2P programs, but it seems a coincidence that it worked fine up until the hdd format and security changes. Can anyone offer any help??