There are three possible causes: an incompatible (HP) printer driver, a
partially corrupt Word DataKey or an incompatible third party add-in.
If you have an HP printer, switch to another printer and test again.
If it is the DataKey, simply delete
HKEY_CURRENT_USER\Software\Microsoft\Office\version number\Word\Data.
The DataKey is automatically regenerated by Word when you next start it.
To see if it is an add-in, test by running in Safe Mode. From Start, Run
(Winkey+R), type in
winword /a
and press enter. Open a document and test for editing and closing now. If it
is OK now, then you have installed something that has placed an incompatible
add-in in Word/Office.
See how to find add-ins
http://www.word.mvps.org/FAQs/Customization/CheckIfAddinsInstalled.htm
http://office.microsoft.com/en-us/assistance/HA011514521033.aspx