If the key appears valid on the portal, the issue likely lies in the connection. Administrators should test the connection from the Connection Server to the internet. This involves checking proxy settings within the Horizon Administrator console (under Product Licensing and Usage ) and ensuring that firewall rules allow HTTPS traffic to VMware licensing endpoints. For air-gapped environments, specific offline licensing procedures (using license files rather than keys) must be followed.
Sometimes an "invalid license" error is triggered by underlying certificate or connectivity issues rather than the key itself: Cloud Connector Sync: Ensure the Cloud Connector can reach the Omnissa/VMware portals horizon connection server license key is invalid
Verify the Connection Server's SSL certificate has the friendly name If the key appears valid on the portal,
He started with the basics. He checked the logs. DEBUG (0A4C-12A0) License key is malformed or signature check failed. DEBUG (0A4C-12A0) License key is malformed or signature