Just bought MCC, matchmaking not working

I just bought MCC with the purpose of playing halo 3 multiplayer. I’m on PC via wired ethernet connection, and the game just keeps giving me issues either when 8 players are found and matchmaking failed, or I load the map half-way and it tells me connection failed. This makes no sense to be since I play various other multiplayer games with no issues at all. Does anyone know a solution?

I’m not sure how to get around this…

Connection status -
Internet conntion: connected
XBL services: up and running

Performance -
Lat: 85 ms
Packet loss: 0%

XBL multiplayer -
NAT: Teredo is unable to qualify
Server connectivity: Blocked.

Attempted:

  1. Fix it feature
  2. Checked Windows Firewall is enabled and that default policy is active
  3. There are no security software that could be causing this.
  4. Windows services required for XBL party chat and multiplayer gaming are set to default values
  5. Time and date are accurate and set to automatic.
  6. PC does not have a firewall rule blocking Teredo network connectivity.

I’ve also set teredo server to: teredo.remlab.net and didn’t work…

Now I’m at:
C:\WINDOWS\system32>netsh interface Teredo show state
Teredo Parameters

Type : enterpriseclient (Group Policy)
Server Name : teredo.remlab.net (Group Policy)
Client Refresh Interval : 30 seconds (Group Policy)
Client Port : unspecified (Group Policy)
State : probe (secondary server)
Client Type : teredo client
Network : managed

Still getting this:
NAT Type: Teredo is uanble to qualify.
Server connectivity: Blocked.