If the printer is printing purple from files outside of PSP and oddly from within, I'd say that the problem may be the printer itself. Make sure you have the latest drivers and that your connection to the printer/scanner is clean. If using USB then disconnecting other USB devices if you have any may help. If using the wireless method you may try changing channels. Make sure that the ink is seated properly. If you're specifying paper type you may try the default.
Does a test or calibration print come out right?
Also, try putting a file onto an SD card (or other media that the printer takes that you own), inserting the card into the printer, and see if you still have the issue.
"Smoke me a kipper, I'll be back for breakfast."