Some Outlook 2007 users are having problems printing calendars with the events colored with color categories. In many cases, the problem printer is an HP and its correctly configured to print in color.

HP support has this to say:

Some or all of my jobs print in monochrome (black) only. How do I change this?

If a software program, such as Microsoft Outlook, is restricted from printing in color, embedded documents in e-mail files will be printed in black (monochrome), even if the application would otherwise print in color.

Yeah… right. If this is true, then Acrobat is also restricted from printing in color, because printing the calendar to a PDF (which has the correctly colored appointments) then printing the PDF also results in no color on the appointments. Yet printing the same PDF to a different printer results in colored appointments and printing other PDF’s containing color works on the HP. Printing email that contains colors works, so it’s not a restriction in Outlook.

You can try changing Outlook’s option to print with gray shading. It doesn’t make a difference for me. (HP 990c)

1. Go to File then select Print
2. In the Print dialogue click on the Page setup... button.
3. Uncheck Print using gray shading (near bottom of dialog)

If printing color categories is really important to you, you may need to replace the printer. While I don’t know which printers are affected, I know calendars with color categories print correctly on my Oki color laser.