My guess is that it is not a Word problem, but a Windows problem. There is a counter that appears on the status line (bottom of screen) when a document is being queued to print. If it counts to 84, but printing stops after 8 pages, there is a problem in how Windows is communicating with the printer.
Get into the printer properties. (Click the Start button, click Settings and select Printers. Right click on your printer and choose Properties.) If the setting is to spool, try changing it to send the file directly to the printer.
(Note: if that works, you might want to change it back unless you are frequently printing large documents, because this setting does not let you do other tasks while printing in the 'background'. - sort of ties up your system.