Internet Connection Sharing

[HeyRobi]

Ok I need help. I installed the reg hack to adjust the settings on my phone for ICS and then connected my phone to my "LAPTOP" with active sync running. I open ICS and hit connect it connects I surf the web no problem. I then do the same exact thing with my wifes "LAPTOP", no problem. Then I tried to connect to my "HOME PC" and it says its connected on my phone but no internet. I do the same thing with a coworkers "HOME PC" and no internet. Now I don't think there should be a reason that it works on my laptops and I cant get it to work on a pc. But crap I cannot get it to work for some reason. I am using XP on all computers except for my wifes laptop she has vista. I am using the same phone on all of them. Can someone give me some ideas? Firewalls, ports, anything..... ?