Unity 5.3.4f1 License Error

When I open Unity 5.3.4f1 for the first time, I sign into my account and I get License Error and it gives me the option to Re-Activate so I click that and it says “Checking license” then it goes back to License Error.

How can I fix this?

There seems to be a Workaround by using a “Manual activation” - disconnect from the Network, start unity and follow the steps to manually activate unity.

Found this solution here.

Hello, I had the same in Windows 10, and I just had to run Unity as Administrator. Hope it helps.