OK, now it's time to make a little mention on what the DOT4 thing is, when you talk about printers.
When you take a dive into HP windows drivers, you will most likely get to see the contents of it's .inf file soon. Almost every printer being listed there has a DOT4 text in parentheses somewhere at the end of the line. One could thing it would be a simple wikipedia search, but that gives you back an article about breaking fluid :-), then you search a couple of hours and you get there:
DOT4 port is a virtual port windows uses for communication with printers. In general, there is one port for each feature of the multi functional device. Printers usually need a driver that helps windows to structure the information for the printer in a way the printer understands. The data for the printer then flow through the certain DOT4 port that is responsible for the certain printer feature.
Happy printing!
