Thanks for reaching out! I'm sorry to hear you are experiencing issues connecting to a newly installed listening tentacle. To troubleshoot this issue further can I please get you to perform some additional troubleshooting steps?
Firstly, from your Octopus Server, can you please get the Tentacle URL that Octopus is using to communicate with the Tentacle? Typically, it's using TCP Port 10933. If you can login to the Octopus Server, you can open a web browser and navigate to the Tentacle's URL, eg: https://TentaleIPorHostname:10933. With this Test, I'm interested to see if you get a web page response back from the Tentacle.
If the connection times out or you don't see the page: Octopus Tentacle configured successfully, Can i please get you to ensure your Octopus server has end-to-end network connectivity with the tentacle? For more information on troubleshooting the Tentacle communication, for more information on troubleshooting tentacles, please check out or documentation on Tentacle Troubleshooting