When I try to transfer a caller I hit *then the ext but I get an error they says address incomplete any ideas ?
Thanks!
How have you set up your system such that you think *(whatever) will transfer a call?
how would someone go about doing that ?
How would we know? He did not tell us what kind of system or phone.
Typically you would hit the transfer button on your phone if it has one. If the phone does not have a transfer button the default transfer code is ##.
And any in-call dtmf sequence that was only one digit long in "featuremap would be just a monumental screw-up just waiting to happen 
how do I setup that ? dtmf sequence ?
Your original post was that calls would not transfer when you dialled “*(the extension)”. Unless you set up your system to do that then it jut won’t use ## or *2 if that doesn’t work then dial ** on your current call and then read the next bit:-
Sorry linuxman nobody here will “read you the manual” please read all the documentation available until you know.:-
a) what dtmf means
b) what a sequence means.
c) how to change the default in-call feature codes.
For a) and b) then I suggest http://vopi-info.org and if that fails you http://google.com. A clue for c) is that it is all in the GUI (FreePBX) and this GUI has in-line help for almost everything if you just “hover over” the right bit, you will unfortunately have to read those nuggets.
You still never told us what software and what kind of phone. Your communications is almost incomprehensible.