I have a SAML21 Xplained Pro board with me. I connected with Atmel Studio7( 7.0.1931). Drivers are installed for the board. I could see under device manager.
Tool also getting listed in the Atmel Studio. But serial number is not shown. See below image: Serial Number Not Shown.JPG.
Also tired to upgrade the firmware where usb enumeration fails. please find the attached image (USB Enumberation Fails.JPG).
Kindly provide some solution to over come this issue.