» Sat Jun 26, 2010 8:07 am
It would help if you first told us if you were trying to play online from behind a router, and if so, what the brand of the router is.
In terms of general advice here is the xbox live support article on what ports to open.
http://support.xbox.com/en-us/pages/xbox-360/troubleshoot/kb/xbox-kb.aspx?kbid=908874
BTW a simple google search could have shown you this, you have google in Denmark, right?