We're excited to announce that we've fully migrated the Xbox Forums to their new home, here on the Microsoft Community forums!
As of today, going to forums.xbox.com will redirect you here to the Xbox area of the Community forums. We've moved all of your existing threads over so you can continue and start conversations with the new forums experience.
We sincerely appreciate the feedback you have provided over this transition and can't wait for you to check out the new Xbox Forums!
if you are using a slim and it detects an ethernet cable connected it makes it the default connection and looks to that for connection to LIVE..you might want to search the support pages to see if you can use the wireless with an ethernet cable plugged it