If you have only one parallel port and need to connect two printers check to see if one has an ethernet port with an RJ45 connector, if so here is what you do:
Connect up your parallel port printer as needed and install as neccesary with drivers and such.
Find yourself a cross-over cable and and extra ethernet card, and manually connect up the second printer to the new network card.
Manually configure the second ‘Local Area Network Connection’.
Most probably the following setting will work on a Windows~ machine.
DNS: <leave empty>
Follow the instructions to setup your ethernet card connected printer with the following configuration:
Now add the new printer by Control Panel > Printers and Faxes, choose Local Printer but do not click the attached directly button.
Click next and then create your own port at the bottom by chooing TCP/IP.
Click next and just type 192.168.2.2 in the IP Address box.
Click next and you should instanty be shown the new printer successful install page – click Finish to Finish.
Thats the best way, you can then share those printers on your locally connected network. The serial pors for printers are useless and parallel port switch boxes are just very inconvenient on a network with more than one PC or laptop.