PCL 6”, but it is a version-2 driver and Windows 2000 prefers to use a version-3 printer driver when it is available. So
in this case, because the print server at the remote site has a matching driver, which is version-3, the Windows 2000
client downloads this version-3 driver and now runs this printer driver.
The connection to the remote print server silently upgraded the client computers printer driver to a version-3 driver.
While still at the remote site, the client and server are both running the same printer driver and printing works as
expected. However at Event #3, when the client returns to the home office and tries to print, problems occur because
the printer driver being used on the client is not the same as that being used on the server and these two printer
drivers are incompatible with each other.
Figure 81: Introduction of incompatible printer drivers through a silent driver upgrade
The example illustrated in the following figure is similar, except in this scenario the client first makes a connection to a
Windows 2000 server with the version-3 “HP LaserJet 4000 Series PCL 6” printer driver. Initially, because client and
server are both running the same printer driver, printing works as expected. However, in Event #2, the client makes a
connection to a printer that also uses a “HP LaserJet 4000 Series PCL 6” printer driver. But the printer driver on this
NT 4.0 server is a version-2 printer driver. Because the client already has a matching printer driver that is version-3, it
just continues to use this printer driver. If these version-2 and -3 printer drivers are not compatible, then printing
problems occur when trying to print to this second printer.
Software Technical Reference ENWW Print server operating system migration 209
