Device or computer could not be verified
Solution 1:
Just had this problem. Not sure what exactly had helped, but I
- Went to the Network Preferences and deleted whatever I could, all the locations except the one left and for this last deleted all the interfaces.
- Rebooted
- In the Network Preferences created a new location.
After that everything started to work again. Probably you could just delete and recreate your Ethernet interface.