Can't connect to TWR-KV31f120M

[GaryOlmstead]

I have two TWR-KV31F120M boards.  When I connect a USB cable to either board, the power LED comes on, but I don't get a "USB Drive Detected" pop-up window, and Windows 10 Device Manager never shows a Ports(COM and LPT) entry. MCUxpresso 11.5.0 can't make contact. Hitting Reset doesn't help.  It doesn't matter if the Tower elevator modules are in place or not.

With the same cable plugged into a FRDM-KV31, I get the pop-up and Device Manager Ports entry, and MCUxpresso contact, so I know that the computer and cable are OK.

Any suggestions?

[GaryOlmstead · Accepted solution]

Never mind, I figured it out (had to reload the bootloader).  Both boards work now.

[GaryOlmstead]

Forgot mention that I have double-checked that ALL jumpers are in the default position on both boards.