People posting to web forums - in order for others to help them - need to really understand that such a broad question put this way with no other supporting information is impossible to answer. There are many factors which could be causing this and readers know nothing about your print set-up and your working procedures. You need to provide a detailed description of your printing process, all your settings, your profile selections in the printer driver and the software, how your display is calibrated and profiled and with what parameters, etc. As well, if you don't yet know what you don't know in order to specify these factors, you should do some learning and reading in order to pinpoint your problems more precisely. For this I would highly recommend the Reichmann-Schewe "From Camera to Print" download video tutorial. It is reasonably priced, accessible, and takes you down the learning curve as quickly as anything can. Watch it, see if anything said there helps you detect what may be causing your problem, and if you still have trouble, by all means come back to the Forum with a clear description of the context in which it is occuring. Many including myself would like to be helpful once we have a clue where to begin.