Problems With Lan Games

[Heritic1]

Having Problems when trying to connect to computers through Lan, it recognises that there is a game there but when trying to join it, it says that there is a connection problem, all other games are still working fine.
Any help on this problem would be welcome

[Artas1984]

LAN does not work at all. Stupid design, 10 out of 9 games work, but not this.