I'm having a number problems with one of my printer servers. When I start
ndpsm.nlm I get:

'Error (-916) occured while initializing Printer Agent "unknown". (NDPS
Manager internal Printer Agent ID 460BD982). Program execution may not
continue normally'

This happens on two other 'unknown' print agents. One of the two print
agents here displays error -812.

I then press ESC to continue loading and then it seems to work, ie I can
still print. But, when I manage the print manager via imanager I get;

'Service Error: Unclassified server error
Service Other Error: FFFFFC6C
Service Other Error2: 0
Object Identification: .Print_Manager_Corona.NDPS_Printers.soas.ac.uk'

Looking at the print manager via NRM shows three 'unknown' PA's.

My initial thought was that the database was corrupted, so I followed a
number of TIDS to remove the corruption but the problem was not resolved.

Searching for the error codes showed;

Error code -812 - NDPS E OBJECT NOT FOUND

I can see that I need to remove the unknown objects referenced by the
print manager, but how do I do this?

The print server is NW65 sp7.

Thanks in advance.