I recently connected my Xbox 360 to my college campus's wired network, which requires me to use a static IP Address. Since then, almost every time I turn on my Xbox I am not connected to Xbox Live. The only way I have found to connect is to attempt to connect, invariably fail, test my network connection (which signs me out and always succeeds) and then sign back in. Doing that has connected me to Xbox Live every time.
I have tried just signing out and back in, and that does not work. This problem did not happen when I was connected to a part of the network that used DHCP.
Is there a setting I can change to avoid this, or is there at least something simpler I can do to connect to Xbox Live?