For info:

I was trying to upload a new driver for the HP LJ2420 printer. I kept getting an error NDPS Library Error Category: 1060004h, Other Error: FFFFFC63h.

In my case I was trying to replace an existing driver. My solution was to first delete the existing driver from the broker, then uplaod the new version of the driver.

I'm sure I came across this before in past but had forgotten - so now its here to remind me and anyone else. For info this was the latest iprint patch b running on nw65sp7 with client version 4.36 on MS winXP.