This problem may be caused by:

• The print management service has not started. You can check the status of the print management service via the Web management interface. Note: In the Windows Terminal Service window, the status displayed may not be correct. You have to select "PrintUsage Service" in Administrative Tools -> Service to ensure it has started correctly.
• This print server has not been added to the Web management. Login the Web management interface to ensure the print server is listed.
• This printer is not being monitored. Add the printer from the “All Printers” page of the web management.
• The print monitoring service has not been restarted after adding printers from Web management. If a new printer is added or any other changes are made to the print monitoring service, it must first be restarted before these changes can take effect (System will prompt whether a restart is necessary).
• The Windows printer name has been changed. Changing the printer name could also cause the failure of printer monitoring. To resolve this problem, you will need to add the print server and printer again to the system or change the name of the printer back to how it was before.