Make sure your OS supports ISPmanager 6. Read more in the documentation.

If the OS is supported, you can upgrade ISPmanager 5 to ISPmanager 6.

Navigate to Settings → System Settings in ISPmanager and check if auto-update is enabled:

If auto-update is disabled, update the panel to the latest version manually. If the version of ISPmanager is lower than 5.295, you must upgrade twice: first to the latest version of ISPmanager 5, and then to ISPmanager 6.

If AutoUpdate is enabled, the server will update the license automatically within 24 hours.

You can update the panel following to the instructions in the documentation.

If the OS is not supported, you will need to migrate the ISPmanager panel to a new server with the supported OS. To do this you need:

  1. Install the panel on a new server.

  2. Activate the Trial License.

  3. Import all user data from the old server to the new server.

  4. Bind the Control Panel license to the new server.

Detailed migration instructions are in the documentation.