Engaged tone on forwarding calls

[scutt]

Our receptionist receives a call to transfer, she presses the transfer button, enters the extension. At this point the caller hears the engaged tone, and the call can not be transfered.
Does anyone know what is causing this...it is only on this particular extension.

 

[tspronsen]

If you hear the engaged tone you are not be able to transfer a call. You can only transfer a call to an engaged extention if 'call waiting' is enabled. In that case you hear a ringing tone if you call an engaged extention. The engaged user will be allerted that a second call is waiting.