Many users find that the license cannot be activated successfully when they just start to install the 3CX phone system or renew the license, you can refer to the following suggestions to check it out:

  1. Please make sure that the 3CX server is using the latest version, if the version that is too old, it will not be able to connect to the activation server:
  2. Ensure that the license information is complete and is in the correct format, e.g. the email address contains the @ symbol.
  3. change the dns server address as 8.8.8.8. After that, please refer to the below method to check if the 3CX server can connect to port 443 of the activation server:
  • when 3CX is installed on a Windows system, you will simply open your browser and go to https://activate.3cx.com and you should see a blank page without any error messages.
  • when 3CX is installed on a Linux system, you will first connect via SSH and run the command: ‘wget https://activate.3cx.com’, then you should see that the request was successful and display a 200 OK status code and a 0KB file size being downloaded.

After using the above methods, the activation will usually be successful, if it still fails, You can switch to another browser to refresh the license or clear the current browser cache and try again.