How to invite my friend in Desert Ambush ?

[metalcraze]

But that method for reason unknown does not work for everyone, it's then possible that despite having set up the IP correctly your friend will never see your server, even if trying to disable his firewall (not recommended).

Most likely cause is the crappy Windows Firewall that unfortunately many people do not have disabled by default.

[Incubus]

Thanks Incubus.
I was wondering if :
Are 1.96 servers compatible with 1.99 ones ?

sadly no as Matteo said, but u can downgrade ur game somehow as far as i know.
theres not many 1.99 server in air. esp. 5 active atm.