I am trying to activate ESET software on an endpoint (client workstation)

Invalid License. To receive the quickest support response, provide a valid License (Key, Public ID, Username). If you don't provide your License, your support request will still be submitted but may take longer.

To display your License ID, open your ESET Product and click Help & Support in the left sidebar. See our Knowledgebase article for step-by-step instructions.