I've posted before about this, but we have narrowed the cause down to a
THIRD party. Here is a summary of the problems so far:

We are using NetWare 6.5 SP2 on our servers and - for the most part -
Windows XP (SP1 and SP2)on the workstations. This Summer we set up our
school to print entirely using iPrint (originally the client that came
with 6.5 SP2). With this client, we started getting complaints that when
users were in Microsoft Word, an hourglass was popping up every three
seconds and while it was up any keystrokes or mouse actions were lost.
It was suggested that we upgrade to the iPrint client version 4.11 and we
did so in September. The changes noted were that the hourglass appeared
every TEN seconds and while it was up the keystrokes were NOT lost. The
hourglass proved to be a major distraction, though. Mouse action was
still interrupted.

We examined the problem more closely and noticed that all our
workstations that were set to print to HP printers were NOT seeing the
hourglass. The majority of our networked printers, however, are Brother
HL-5070N. It is the workstations that are trying to print to these
Brothers that are getting the "hourglass". The Win2000/XP drivers that
get loaded by iPrint include a Brother spooler that apparently is the
cause of the hourglass. We are investigating a Brother utility that lets
you partially unload parts of the drivers, but this doesn't help us with
the iPrint driver loadout.

Larry Woodworth
Net Admin, Osbourn High School
Manassas VA 20110