Imunify360 activation fails in Plesk: Servers limit exceeded for key

Symptom

• Imunify360 extension cannot be activated with a license purchased from Plesk.

• The following error is shown when accessing Imunify360 extension:

  PLESK_ERROR: Servers limit exceeded for key <KeyNumber>

Cause

Imunify360 license can be used on one installation at a time.

The error may appear due to one of the following reasons:

• More than one Imunify360 is are activated with Imunify360 license.

• Imunify360 has been reinstalled on the same Plesk server, thus the same server to be registered twice.

Resolution

If the old server where Imunify360 is activated with the mentioned <KeyNumber> is still online, run the following command to unregister Imunify360:

# imunify360-agent unregister

If the old server is offline, contact CloudLinux Support for further assistance.