On our Sratagy DK280 we have DDI that rings engaged constantly. However if you ring the extension number from internally then it rings o.k. but as soon as you dial the numbers DDI its gives an engaged tone.

Has anybody seen this problem before ?

Define "engaged tone"..........

busy tone ?

Is this on a T-1 or PRI?

Make sure the DID number is pointed to a valid extension number. Also, double check program 17.

Sounds like the DID number is not hitting your switch.....or the DK is rejecting it.