Where did you get that driver? What model is it actually for and what version is it?
That option doesn't exist in the GPD (PS and PCL) or the native PS or PCL driver (Win 7 x86), which may be why it is grayed out.
It is possible, but unlikely, that Acrobat is the issue, it may be controlling color. So check that Let Printer determine Color is selected.
I am using a WorkCentre 7428 in Windows 7. I am trying to adjust the contrast of a black and white PDF printout, but when I go to Print>Properties>Advanced tab>Image Options, Grayscale is grayed out. I have tried changing the options in the Color Options tab, selecting "Print in grayscale (black and white)" in the Print dialog box and adjusting some of the Acrobat options with no luck. Any suggestions appreciated.
