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TN - 1321 Unable to activate license with message "Unable to communicate with the Activation Server." For only one license serial number.



This article from InSource shows how to resolve a failure to activate a license with message "Unable to communicate with the Activation Server." for only a particular license serial number.

  • Author: Peter Farrell
  • Published: 12/21/2022
  • Applies to: All versions upto and including 2020x


Unable to activate license with the following message

"Unable to communicate with the Activation Server.
Ensure you have internet connectivity or proceed with offline activation by changing the activation settings."


If you are able to activate other serial numbers from the same License Server, but keep getting the above message for a particular serial number it is possible that the license serial number for which activation was being attempted has already been deployed at a different version release of the same serial number. The message presented is somewhat misleading because the license server could be reached for other activations.

You can check your License Server and look at the License Summary.  If you see the same serial number with a dash # which is different, this could be the issue preventing activation and the misleading warning message shown above.  The dash # appended to the serial number indicates that the serial number has been upgraded either functionally or to a later version.  A dash number of 0 would be the original issue of the license.


If you find that a particular license serial number has already been activated, you would need to deactivate the license or purchase a new license with a different serial number.