The problem is solved. The computer is a Sony Vaio that only has one COM and one LPT. I install a 2 COM + 1 LPT card that was using on the old computer. If I use the "original" LPT port I can do CW. If I use the "new" LPT it doesn´t... so now the printer is on the "new" one and problem is solved. Thanks to all for your help. 73 de Ramón, XE1KK