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How about telling us which software you're using to print the greeting cards and then maybe we can help.
I have nightmares printing cards and practise on plain paper first, making a note of which would be the 'glossy' side and the direction put in the printer. Admit it takes several attempts.
OK... you're printing directly from the iPhoto program. The version of iPhoto you're using (9.6) is an older version and iPhoto is no longer being supported by Apple. It was replaced by "Photos". Let me see if I can find a tutorial for you to follow....
OK, try following this tutorial. You also might want to practice on plain paper as recommended by Sue before printing your cards.
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