Error: The license key is invalid. In order to use the Panel, please obtain and install a new valid license key.
Your license key has expired. To continue using your Panel, you must purchase a non-expiring commercial license key.
There's nothing to be alarmed of, you just need to login to Plesk control panel and update your license.
For Plesk 9.x:
1. Click on Settings > License Management.
2. Click on Retrieve Keys.
For Plesk 10.x:
1. Click on Tools & Settings > License Management.
2. Click on Retrieve Keys.
