Pan-sharpen error

Ice Age Mark

Hello,

I'm trying to pan-sharpen an area of color 4 band 1m resolution NAIP imagery with a smaller area of 60cm 1 band grayscale imagery.  I get an error of "No valid colors found within the specified area..." for the NAIP image.  What does this mean and what is wrong?  It's a 4 band color image and when I click on a pixel with the Feature Info tool I see 4 "valid" bands (colors) and their respective values.  How do I do anything about this error?

Thanks,

Mark