So far printer file HPLJ-4.PRN work fine with HPLJ 2200D, but...I can not get duplexing to work from XyDos. Custom Guide says set default with df jb=x, where x is either 171 (long edge -- which I think means legal size) or 172, short edge, which I think is letter?At all events, no duplex...yet. Thank you. Michael Norman