I have just installed a new Operating System. Why is my license failing to activate?


  • I have just installed Windows 10 on my computer.
  • I just updated my Operating System
  • On opening Unity, I receive an error and it will not activate.


Unfortunately, sometimes our licenses are confused by a change in OS - essentially, it tricks the license file into thinking it is being activated on a new machine, which can cause problems if you have already maxed out your activations.


If you have Unity Personal Edition, please follow this process:

1) Uninstall Unity

2) Delete this file:

* Windows: C:ProgramData/Unity (If the files are hidden, you need to click View and tick the Hidden Items check box.)

* Mac: Library/Application Support/Unity

3) Restart

4) Download Unity again from our website

5) Reinstall, remembering to select ‘activate free version’ when prompted.

If you have Unity Pro, please send your serial number to us here and we will force a return on your previous activations to clear the license.

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  • 0

    It was enough to delete the license file *.ulf, then activate free, run unity, and activate pro/plus (license check still hanged, but you can close it)

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