There are few reasons the printing icon is disabled under your photo. Your photo probably doesn't meet the requirements:
- Photo file has to have full EXIF data included
- Photo has to be at least 180 DPI
- Photo has to be at least 12 Megapixels.
So for example you won't be able to print a photo taken with your phone, because phone cameras usually take photos in 72 DPI - which isn't enough to print a decent quality photo.
We block the printing icon on photos that don't meet the requirements, to provide best possible print quality. You wouldn't be happy with a blurry, pixelated print, would you?