DM-41X USB Disk Missing

[GerryS]

SOLVED

Good evening everyone. I'm sorry to bother you all with this, but I've gotten no response from Swiss Micros and I'm very frustrated. Back in 2019/2020 I bought a DM-41X. It worked great except the USB disk would not show up on my Win10 PC. I tried to fix it then but with no tech support and unable to find any information on this issue, I gave up and lost interest.

Yesterday, going through You Tube, I ran across the 2020 HHC presentation on the updates to the 41X. I pulled out my 41X and ran into the exact same problem, no USB disk. I thought the new firmware might resolve the USB Disk issue. I tried a couple of USB cables which made no difference and out of desperation, I dug up a longer USB cable and the USB disk appeared on my laptop! So it appeared to be the cable. But after a couple of connects and disconnects, the USB drive stopped showing up again. To add to the troubleshooting, I also have a DM-42 and it too doesn't send a USB disk to my PC.

Here's what is weird. I went ahead and did a firmware upgrade on the 41X using the bootloader procedure (what a complicated process) and it worked! So now I have DMCP_flash_3.20_DM41X-2.1 firmware installed but it didn't fix the USB Disk problem.

I'm thinking there is a hardware issue with the DM-41X and DM-42 but both calculators work fine otherwise. I have reformatted and tested the USB memory and it all reports on both machines as fine with no bad blocks.

If anyone has a suggestion, I'm all ears. I'm thinking of trying a new USB cable to see if that makes a difference, but I'll have to go out and buy some.

Thank you for your time and suggestions,
Gerry