What kind of firewall are you using? Is it the standard Windows one or a third-party one? What IP address does your secondary network port end up with? Is the camera in its factory configuration or is it possible it was configured for a fixed static IP address? If the IP configuration on the camera doesn't match the IP configuration of your network adapter then it will not show up in MAX. The Basler software includes a utility that will allow you to change the defaultIP configuration of the camera. We generally recommend the camera be setup for DHCP and link-local addressing, and the PC be setup the same. Then if the two are connected directly to each other they will both get link-local addresses (169.254.x.x).
Let me know some more of the details about your setup and we should be able to figure out what to try next.
The firewall is the standard windows one, the camera is straight out of the box, and the secondary network port ends up with an IP of 169.254.x.x for the computer. In one of the other threads I saw that the windows firewall isn't capable of handling the GigE protocol -- does this mean I should just get one of the Intel Pro network cards?
The Windows firewall is unable to accomodate the GigE Vision protocol but it only affects your ability to acquire images not to discover the camera. Also, if you are using the NI High Performance driver (with an appropriately-supported network card) then this firewall restriction doesn't affect acquiring.
To diagnose what may be happening please try two things. First, go to the command console and type "route print" and attach the output here. From this it may give some clues as to what is going wrong. Also, if you can download a copy of Wireshark and have it do a network capture on the network interface the camera is connected to while you have MAX open and the Devices and Interfaces tree expanded and attach the capture that as well it should give some better details of why the discovery doesn't seem to be working. If you can power-cycle the camera at some point while doing the capture that will also yield some additional clues.
You should try removing the computer from the network if you are unable to shutdown the windows firewall.