Setting up a LAN server

[BlueSean]

I've downloaded all the files for srcds and configured the server to work, however.

I have two IPs, the one assigned by my network and the one assigned by my ISP. If I use the IP assigned by my ISP I have to change the way my network uses TCP/IP connections, (As every guide tells me to do) thus disabling my internet connection. If I leave my IP set as the one assigned by my network, I can't launch the server (I get a "Couldn't allocate dedicated server UDP port" error)

Now, if I launch the server using the IP from my network, or if I disable my net connection to launch it using my ISP IP, the server only shows up on my computer, and only if I add the IP and port to my favorites list.

I have it set in the favorites list on another computer and it always gets <not responding> and even if I have it set as a LAN server in the config file, it doesn't show up in my list of LAN servers.

Can anyone give me some help here? I only want it to be a LAN server, so I can have a LAN party this coming weekend.

Edit: Before anyone asks, I've already forwarded all ports, and just to be safe I've done UDP and TCP 1200 and 27000-27039

[Goofy666]

Make sure you have ALL of these ports forwarded:

Goofy666 Wrote:[UDP] 1200 (used for Steam's Friends service)
[UDP] 27000 to 27015 (so that means all ports in between too)
[TCP] 27030 to 27039 (idem)
=> these are all Steam related ports

[UDP] 27015 and 27020 (default DS port, also used for HLTV)
[TCP] 27015 (you want to forward this for RCON access)
=> these ports are used by the dedicated server itself

http://www.srcds.com/forums/showthread.php?tid=585&pid=2750#pid2750

My guess is you forgot to forward 27000 to 27015 (UDP).

[BlueSean]

Nope, all ports are forwarded.

I'm using a D-Link 624 Wireless Broadband Router via a network cable, all ports are forwarded and I have no other firewall present.