com port changes during upload

Windows 10, D21G board, 24v power supply

When I try to upload a sketch, the com port changes right as the screen flashes on my unit.  The IDE (1.8.9) says uploading, the screen pulses, the port changes, and then after a few seconds the IDE reads "Couldn't find a Board on the selected port".  If I try to change the port in the IDE and upload again, the console reads "Uploading..." endlessly. This happens with every sketch I try to upload.  I cannot attempt to upload another sketch without resetting the unit (double click S1).

Everything was working fine yesterday and I've tried with two different machines and switched out cables.

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Asked on 6/6/19, 2:29 PM

Hi, can you still upload a sketch when you activate the bootloader manually by double clicking the reset button?

Could you try with the standard Blink sketch (change LED_BUILTIN to 26, the LCD backlight) and send us a screenshot of the console with the error, after enabling 'verbose' mode in your IDE preferences. Please send to so we can check what's going on.

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Answered on 6/7/19, 6:40 AM

Thanks Tom, I sent an email. Appreciate the quick response!

on 6/7/19, 3:19 PM

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Asked: 6/6/19, 2:29 PM
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Last updated: 6/7/19, 3:20 PM