I've been struggling with the problem since I got my new 360 a couple of days ago. I'll start with my system specs:
Brand new Xbox 360 elite.
Dell Optiplex 755, 4gb ram, 2.4ghz core 2 duo, NVIDIA geforce 7600gt, ATI HDTV wonder tuner card
Vista Ultimate SP1 fully patched, installed myself from a clean HDD (i.e. no OEM software),
Linksys BEFSX41 router
Netgear 10/100 Switch (not sure of the model, but it has no firewall or security and has worked for the last 6 months with no issue)
Two Apple airport express wireless access points, one to create the wireless network, another to connect the 360 to said network.
all firewalls turned off (on both PC and router), all antivirus software uninstalled.
no fingerprint identification software of any kind (I mention only because I had seen this as a potential cause of my issue)
file sharing enabled, and xbox selected as able to share files from Vista PC (though this didnt appear to be necessary)
So, here's what happens
my Vista machine sees the xbox on the network and recognizes it as an extender. I begin the registration process on the xbox and get the 8 digit code just fine.
I enter the code in media center, and step through the activation process. all the check boxes check, the synch completes, and I am prompted to run a network check. network performance comes back as poor, but suitable for analog tv. Good times. I walk over the to xbox.
I see nothing but a "contacting..." screen which eventually times out. reboots of either system does not change the outcome
there are no errors reported in any of the vista error logs
if I go to test the media center connection from the xbox system menu, the test succeeds.
if I go into extenders in media center, it indicates the xbox is connected and ready to use.
but no matter how many times I try to connect, i cant get past the "contacting" screen on the xbox.
I brought in a friend's dell inspiron laptop with vista home premium, and the xbox connected up to it's media center just fine on the first try. so the problem has to be a setting or issue somewhere on my vista ultimate pc.
here is what i have tried, none of it has worked
restarting ther upnp device host service
reboot after reboot after reboot
deleting connection on both ends, following miscrosoft' exact procedure, regenerating the key and redoing setup (countless times)
trying both nodes on the netgear switch, with linksys router disconnected
trying both nodes on the linksys router with netgear switch disconnected
trying one on each
connecting the two machines directly with a crossover cable
disabling the NIC on the Vista pc and using a USB wireless adapter
connecting the xbox directly to the wired network (instead of wired just to the Airport Express unit, and then over wireless)
Incidentally, I should mention that if I run a network performance test from media center with the xbox on the wireless, i get about half way up the performance meter. With the xbox either wired directly to the LAN or to the MCPC with a crossover cable, the network performance is so poor that the performance tuning test times out. One bar at best. media center, xbox live, and pc connection tests from the xbox all work fine when hard wired or cross-over (of course no xbox live with the crossover).
this led me to believe I had cabling or Nic issues, but i tested the cables out with large file transfers and they all worked just fine, and got throughput i would expect on a 10/100 network. Also as I mentioned I tried disabling the Vista NIC and going with a usb wireless adapter, but it did not help.
Does anyone have any idea what might be happening here. what setting might be screwed up? I'm totally at a loss here. I really dont want to rebuild this system, which is pretty much empty anyway save for the OS and drivers, especially if it isnt going to help
Thanks in advance