I know nothing about your environment, but keep in mind that you have to have both the 32 and 64 bit printer drivers installed on your printer server, and those drivers have to be identical in name and version.
I know the script is adding the printers and the drivers and I'm sure the driver (64bit) is on the server. These clients never had these printers (network copiers) that I'm adding, nor any other printer of the same model and I'm removing the printers after the script runs every time while testing it.
