In addition to what Ed replied, I do know that the serial Epson receipt printers require the use of a NULL modem cable. Personally I use the EPSON POS SDK instead of generic printer drivers. This saves a lot of problems.

http://pos.epson.com/pointofsale/opos.html

>Hello All
>I'm having problems trying to print in a POS printer (EPSON TM210, STAR 200...). I've allready installed their on on drivers, generic printer text drivers. Sometimes it works, sometimes gives windows error: "...error writing to LPT1..."
>I'm new dealing with POS printers, is there any TRICK, any driver, special printer port???
>
>Thank's in advance,
>NPedro