Photoshop :: Home Network Print

Our home network is a Vista PC with an Epson 2880 printer attached to the Vista PC. My wife's XP PC connects through our simple network and prints on the Epson printed by going through my computer. Simple set up, no problems. We both use CS4, set so CS4 manages color, correct Epson paper profile, printer color management off, all the correct settings. Both our monitors are color corrected with Spyder3. When she prints from her computer every picture has a magenta cast. Even more strange is when I copy the same picture onto my PC and open it in my copy of CS4 the picture looks normal but CS4 will not print it. CS4 says I do not have a printer attached. I can open any other picture in the same CS4 session and print with no problems. Every time I try to print a picture that she printed CS4 says there is no printer. This occurs even when I have copied the picture onto my computer and opened it on my computer. I have tried renaming the picture and even changing the format to TIFF or JPEG but CS4 still refuses to print it. I can open a new blank document  and use the move tool to move the picture onto the blank document, At this point I can print from CS4 normally AND the picture will not have any color cast?