[Asterisk-Users] OutBOund Dial problem

[kurt x]

I have the following extension (7700)  that can dial out with the below config.

exten => _1nxxnxxxxxx/7700,1,Dial(SIP/${EXTEN}@outbound)
exten => _1nxxnxxxxxx/7700,2,Hangup

If I change it to 

exten => _1nxxnxxxxxx/77XX,1,Dial(SIP/${EXTEN}@outbound)
exten => _1nxxnxxxxxx/77XX,2,Hangup

It does not work.

Any help is greatly appreciated.

Kurt