On Sun, 4 Oct 2020, Will Senn wrote:
  I am using a Thinkpad T430 w/DOS 6.22. If I can figure
out how to get 3.31 on
 there, I'll give it a shot. I bought a Floppy-USB connector for my old 1.44
 floppy drive and it works fine with DOS 6.22, but I'm not sure where to
 locate 3.31 media that I could burn onto a 1.44 floppy and boot. I have
 sealed IBM DOS 3.3 media, but I don't think my T430 is really compatible :).
 So, I'm not keen on opening the seal... 
I'm curious.
6.22 did not have native USB support - that didn't come about until
WIN98SE.
Are you running CONFIG.SYS drivers for it?
If you can find an original copy of COMPAQ MS-DOS 3.31, that was
originally available on 1.2M and 1.4M
Zenith MS-DOS 3.31 is another popular choice.
Try to find it, rather than opening the PC-DOS 3.30.  3.30 (and all
earlier) did not support HDD >32M, although there were ways to cheat that
limitation, such as the network redirector (with MSCDEX) coul make a local
drive LOOK like it was a network drive elsewhere.
--
Grumpy Ol' Fred                     cisin at 
xenosoft.com