DCornish

Hi Fausto,
Thanks for your response. Our previous computers were Advantech Core 2 Duos running 32-bit WinXP SP3, but knowing that doesn't really help very much.
This afternoon, I found the root cause of the problem, and I'm letting you know so you can forward the solution to other customers using old Data Translation hardware in new Win10 machines.
You will recall that none of my three DT-321 boards would acquire ADC data after a power-up or hard reset (red button), but they all worked fine after a system restart (Start>Power>Restart). I experimented with using Device Manager to disable and re-enable the DT321 device driver after a power-up, and doing so also fixed the problem without requiring a system restart.
While researching how to write a PowerShell script to perform a disable/enable cycle on the DT321 device driver, I found a post from another user whose hardware also wouldn't work after a power-up or hard reset, and he had discovered that disabling the Win10 fast startup feature cured his problem. I then tried disabling Win10 fast startup on my new computers, and this solution worked for me as well.
As it turns out, Win10 fast startup performs a mini system hibernation at shutdown, and it works well for modern devices that support hibernation mode at the device driver level. My guess is that the DT-321 is too old to support hibernation mode in any form, so its operation is negatively affected when the fast startup feature is enabled.
TL;DR for Data Translation boards that don't work after power-up or a hard reset:
   1. Suggest a system restart, and if the board works after the restart,
   2. Suggest disabling the Win10 fast startup feature.
Thanks again for your help, and let me know if you have any questions.
Regards,
DaveC