How to clear the print spool

[Windows users]

1. Click "start" and go to "Run"
2. Type "services.msc" at the prompt which will open the Services
   window (ooh, pretty...)
3. Scroll down the alphabetical list in the right window pane until you come
   to the entry with the name "Print Spooler"
4. Right-click this entry, then select "stop". This will stop the computer
   running the process that holds your print queues.
5. Leaving that window open for now, click again on "Start", and then click
   "My Computer" to open a Windows Explorer window.
6. We've stopped the queue service, now we just have to clear the jam that is
   already there. To do this we navigate to the print spool folder which is hiding
   within the Windows folders. Usually Windows is installed on C: drive, but you
   should be easily able to tell when the Explorer window opens which drive it is
   on.
   
   The usual path to the spool folder is
   C:\WINDOWS\system32\spool\PRINTERS, but yours may be slightly
   different. Your windows drive may have another name for instance, but this would
   be uncommon. So click on your Windows drive (usually C), then double-click on
   the Windows folder, and then find the System32 folder and double-click on
   that. Windows may warn you that you are about to view system files, but click
   "View files anyway" message and search out the "spool folder". Within the
   Spool folder is your Printers folder, and you should open
   that.
7. Delete every file within this folder to empty the jammed print queue
   (pressing the "ctrl" and "a" keys will select all files and then you can just
   hit "delete").
8. Close the explorer window now that we have emptied the cleared spool files,
   and return to your Services window. we must re-start the Print spool
   service, and do so by right-clicking the Print Spool entry and selecting
   "Start" from the list. Close the services window and try printing again

If your print spool folder contained no files to delete, then this article will
obviously not be the appropriate solution to your issue.