not recognizing COM port

I teach a high school course using Arduino boards. Over the past 3 days I've had a rash of (3) boards that Arduino IDE is not recognizing when the board is plugged into the COM port. The power light on the Arduino board is on, so it is getting power. Also when we go to device manager and we plug in the USB cable the Arduino board briefly pops up and then disappears.

bikeman:
I teach a high school course using Arduino boards. Over the past 3 days I've had a rash of (3) boards that Arduino IDE is not recognizing when the board is plugged into the COM port. The power light on the Arduino board is on, so it is getting power. Also when we go to device manager and we plug in the USB cable the Arduino board briefly pops up and then disappears.

Did you use the other cable you have? IF so, then the connector on the Arduino boards has a problem.

Paul

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