Adhoc is connected but can't play games?

Question

I'm on XP and so is my friend.
Here are the steps I took

i made ad hoc network according to Microsoft
i set my own TCP/IP, to 100.100.100.1
with a subnet mask of 255.255.255.0
my friend had the same subnet mask and the same ip ending in 2
i disabled my windows firewall.

he is able to connect but when i host something (a cs server for example) and he trys to connect to my ip. He gets no response from my computer

in his wireless settings he has received no packets

Answer 1

Usually when setting up a private network you want to use IPs in the private network ranges. (Particularly when you have an internet connection!)
10.x.x.x
192.168.x.x
so change your ips from 100.100 which are not reserved for private networks to
10.0.0.1 and 10.0.0.2

When your friend tries to connect, he also will need to disable his firewall or specifically allow 10.0.0.1 (if that is you)
Once all is setup, just check that both computers can "ping" the other one. You should then work just fine. To connect to servers you need to have the proper client running on the "client machine".