What do you do when you print job won't cancel?

If it is really serious you can restart the Windows Printing Service under the Services MMC. What I normally find with the HP the following steps fixes it.

• Switch off the printer
• Delete the job
• Restart the Printing Service
• Restart the printer

Sometimes however the restart requires a complete machine restart.

• start
• run
• services.msc
• Find the printspooler service
• restart this service
• Fix missing paper / wrong port / any problem...
• print again

Neither of these suggestions did it, but unplugging the printer, and then plugging it back in did the job.