Unable to install license: The license key is invalid. Different license is shown in License Info

Symptoms

• Unable to install active and valid license key. The following error is shown:

  PLESK_ERROR: Error: The license key is invalid. In order to use Plesk, you need to obtain and install a new valid license key. 
  Your license key has expired. To continue using your Plesk, you must purchase a non-expiring commercial license key.
  

• Info section shows a license key PLSK.12345678.0000 different from the current one and new valid one.

• In /var/log/plesk/panel.log with the enabled debug logging the information about the expired license can be found:

  PLESK_INFO: [2018-01-10 22:32:37] DEBUG [util_exec] [5a5686756623d] Stdin: {"0":"license","1":0,"2":"license_expired","3":{"License":"PLSK.12345678.0000"},"4":{"License":"PLSK.12345678.0000"}

• Also, there can be seen that unknown license always installed instead of the new valid one:

  PLESK_INFO: [2018-01-10 23:42:02] DEBUG [panel] Key handler was called with params Array
  (
  [0] => /usr/lib/plesk-9.0/key-handler
  [1] => /etc/sw/keys
  [2] => reschedule
  [3] => --id
  [4] => PLSK.12345678.0000
  [5] => --update-time
  [6] => 2018-01-20 19::2:0:
  )
  
  
  
  
  
  
  
  
  

• The information regarding the reported license key can be found in the files inside the directory /etc/sw/keys/keys/:

  # grep -ir 'PLSK.12345678 /etc/sw/keys/keys/
   /etc/sw/keys/keys/keyXXdO1gcm: <core:key-number core:type="string">PLSK.12345678</core:key-number>
  

Cause

Incorrect data in the key repository.

Resolution

1. Connect to the server using SSH.
2. Move out the content of the directory /etc/sw/keys/keys/ and rename the registry.xml file:

   # mkdir /root/keys_backup/
   # mv /etc/sw/keys/keys/* /root/keys_backup/
   # mv /etc/sw/keys/registry.xml{,.old}
   
   

3. Reinstall the new key through Plesk GUI.