Below we have compiled the "License Activator's" error messages:
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There was a problem in the creation of the serial number. It seems to be not correct.
Cannot validate license.
This error means that the gateway login and/or the activation key are not correct.
If the "License Activator" application has been executed from outside the plugin (it is a separate application) you will get this error as well. In this case the error appears, because the application has not been used as originally intended.
The system cannot be identified. Cannot detect the system Host ID.
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The communication with the license activation server went wrong. In most cases there is a temporary problem with the connection.
License problem (code -6). Requested version not supported. Please click on the Help button to find out more about this problem.
This error points to a license conflict, e.g. when RealFlow | Cinema 4D 2.0 tries to read a 1.0 license. In this case, remove/rename the 1.0 license file and replace it with you new 2.0 file.