This error message occurs because the license has been entered wrong, you do not have correct permissions or a firewall is blocking the access to the license server.
To resolve this error message you will need to locate your Forecast 5 license file in the following folder:
Note: This may be a hidden folder so you would be best to copy this path into the Windows Explorer.
Once you have located this folder, delete the FRCST5 file and reopen Forecast 5.
You should now be able to register Forecast 5.
Note: If you are seeing the screen below, you are in the wrong place. You will need to go to ProgramDATA, not program files.