You’ve got that backward. a MicroSD card is the recommendation for openHABian, and is the only supported storage format. You can use other formats, and hopefully someone who does will chime in knowing how to get it working. “Supported” just means that we might not be able to help you, since there are so many untested variables in play.
If you haven’t already done so, you might also want to check RPI forums (since this sounds like more of a hardware/Raspbian issue than an openHAB issue).
I get wanting to use equipment that you already have. If you don’t have any luck, my personal recommendation is to:
- Swap out your MicroSD card once a year
- Put your RPi on a UPS.
Sudden power loss is the biggest killer of SD cards, particularly since openHABian uses ZRAM to reduce writes.
Good luck!