Hey, I will try my best to answer all these things
What Country/State/Province do you live in? - Scotland/UK
Modem brand & model number: Virgin Media
Router brand & model number: DLink DI-524
Network Connection Type: Wireless/Wired - Wired
If Wireless, what type of encryption are you using? /
If Wireless, are you using a white or black external adapter, or an internal (Xbox 360S) adapter? /
Things you have tried:
Is UPnP Enabled? Yes/no/Unknown - Dont know
Is NAT Type Open? - Yes
Any Error Codes you encounter: Insuffiecnt MTU settings
What type of internet do you have? Cable/DSL/T1/3G? - Cable
Who is your ISP(Internet Service Provider)? - Virgin Media
After you run "Test Xbox LIVE connection" and click on "More info", what is the exact message shown on screen?
- Xbox live needs 1364 or more MTU etc etc.
Ok so, I phoned xbox up, no help really, but I plugged my xbox directly into my modem and it worked, so the problem is with the router (The router I have been using with my xbox for 3years with no changes -.- )
The guy on the phone emailed me all the ports that xbox need to be open to connect to xbox live.
So I logged onto the router and using a helpful guide opened all these different ports, using the IP address found on my xbox.
I triple checked again that my MTU is set above 1364 - It is, I have tried it at 1365, 1370, 1400, 1450, 1500 - None work
So I am still getting the same error about not enough MTU
Thanks