why doesn't your printer print black? im not sure if you can change the print color, but for some reason my pep has been printing red and it always used to print black. as for what you can do to print it, all i can say is go to a library or a friend's house and see if you can print it there.
You could check the connections from the cartridge to the printer if it's that kind, or try that thing that cleans the print heads. I can't remember what it is called, but that has happened to me and cleaning the print heads helped. It could be also that the cartridge isn't touching the paper when it comes through.