"Machine Identification" invalid error

I tried returning and re-activating the licence on the working laptop. Doesn’t work. Then I tried reinstalling Unity on the not-working laptop and still doesn’t work.

I tried looking in the Unity folder in Program Files and don’t see any *.log files there. On the non-working laptop, it won’t let me get in to manage the licences. In fact, I can’t even sign in.

I get the screen from the below link but the Re-Activate button is grayed out and nothing happens when I click it.

Try deleting the license file. On Mac, it is located at for /Library/Application Support/Unity. On Windows it is C:\ProgramData\Unity