06-09-2014 01:53 PM
I'm sorry to hear you've had issues with a few different printers, but I will certainly do my best to help you with your Envy 4500 not printing black!
I will suggest that you try the steps within this Printer Does Not Print Black Ink or Color Ink, or Prints Blank Pages document as well as this Fixing Ink Streaks, Faded Prints, and Other Common Print Quality Problems document.
Between those two documents you should be able to get the black ink flowing once again. Please let me know how these steps work out for you!