DOS ain't dead

> I have an old Toshiba Satellite S2410 now exclusively running with FreeDOS.
> Luckily it has a serial port for a connection with my OKI Microline dot

Serial or parallel? (imho, paralell)
Check BIOS (is ports enabled?).

If i am not wrong, i remember this printer - he must work from DOS without drivers.
Drivers need for MS-Works for more pretty printing.

Try execute
copy sometext.txt prn:
(File sometext.txt should contains few words like "Hello world!")

(i dont remember all right names)
copy sometext.txt lpt:
copy sometext.txt lpt1:
copy sometext.txt lpt2:
copy sometext.txt lpt3:
copy sometext.txt lpt4:

This take anwser "is printer connected in right way?" (and which port).
And then - try to setup MS-Works.

If printer don't print "Hello world", it will mean problem in BIOS, cable or printer.

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Make DOS great again!

Carthago delenda est, Ceterum censeo Carthaginem delendam esse.