I just recently discovered that none of my HP Printers would print multiple copies of jobs. Regardless of the number of copies I selected through the print dialog, only one copy would be printed without any sort of error being generated.

Evidentially, this is caused by Mopier Mode being enabled on the printer in question. Mopier mode is an HP function which will allow you to produce multiple copies from a single print job. To successfully use this functionality, it requires that the printer be fitted with the required extra memory to store and produce the extra copies local to the printer. Since most standard out of the box HP printers won’t have this, the function will fail and only print a single copy. To fix this problem, simply disable this feature in the device settings tab under the printer properties dialog.