Lately me and my friends have been trying to make an Ad-Hoc network.
I have been trying something that I think should work but it doesn't
seem to. I'll post my methods and all relevant information below, but
let me first explain what happens. When I make the network, it shows
up on my friends (who are windows users) computers, and they are able
to connect, but we cannot ping each other, we simply recieve the
destination unreachable error. Here is what I am trying:

sudo iwconfig eth3 mode ad-hoc essid "mynet" channel 11 key off
sudo ifconfig netmask up

On the windows computer I connect to "mynet" and I set the IP to

ping -I eth3

This yields "destination host unreachable".
Same thing on the windows computer.

If I am forgetting to include something important tell me. Any idea
what could possible be wrong?