The printer is a LaserJet 2550. The computer is running Windows 7 SP1 and Office 2010. Windows describes the printer driver as "HP Universal Printing PCL 6."
Word 2010 prints everything in monochrome. So does Excel.
Outlook prints color. So do non-Office applications.
One of my office mates also uses Office 2010, and shares this problem. Another, who uses Office 2007, does not.
Does anyone know what causes this, and how to fix it?