Your Zimbra Network License expired 24 days ago 🙂
Yes, that message show up when I log in to one of my client and they ask me to renew the license.
Well, the process itself isn’t difficult as what you need to extend zimbra license just ask sales at zimbra.com.
they will email license key and with the key what you need to do is login to zimbra admin.
Click on Global Settings.
Click License will give this screen.
Click Update License.
Browse for license file and click Next.
Your license file is uploaded successfully.
You license file is installed successfully.
Client can continue their zimbra mailbox.