What are the defaults for mc extenders

I have Vista Prem, my 360 can connect to my pc and my 360 shows in the
network window on the pc. but I can't ping the 360 and MC keeps giving a
generic error message (nothing specific just error) after I enter the 8
digit code from the 360. It's my understanding the 8 digit code is only
generated AFTER the 360 connects to the MC pc. Yes I've opened all the
ports listed on the 360, the xbox and windows support sites. BTW I've
got the M$ crap firewall and MC extenders and MC are allowed thru. All
the MC services are running and start automatically. Still no joy!

Any suggestions? Is there any defaults which I need to enable, etc etc.


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danimalhanke