Hi,
I see now, all running on a standalone "server". What type of printer is it? The DB9-DB25 (standard serial) is right, and is COM1 or similar?.
Whats the BAUD rate? So can you do a standard print test to the printer? test on the printer to see what its Baud settings are? Do both settings match?
Can you do a print test from the server/POS unit? If yes, then move to the software. In POSCFG in devices, is your printer type here for Printers? (Epson etc). If thermal 40 col, try Epson TM-T88 thermal and hope your printer will Emulate Epson. If an Impact printer set it to TU-220 and again hope this will emulate an Epson.
If you want to make your own connectors (and join them with a standard CAT5 or CAT6 cable) as follows:
DB 25 DB 9
White 1
Black 2 3
Red 3 2
Yellow 5 8
Blue 6 6
Orange 7 5
Green 20 4
Brown
I dont believe you can use LPT1, and can only use serial