you have to reset your printer
1. Unplug AC (and usb just for good measure)
2. Hold Start while plugging in...
3. While still holding Start press Resume twice.
4. This then allows for Removal of Ink Cartridges(if you are past the limit)... a very important step apparently.
5. Now repeat Step 1... Step 2
6. Now press the Resume 4 times (only blinks for 1st two presses !)
7. Should be ready...
Exact same problems with this printer as the previous comments.My iP4500 haven't seen much use but it worked fine until few months ago when it started telling me that printer head was not installed. It tells me this everytime I started it up to print something. I wrestle with it for about an hour and somehow I get it to print something. It has become very annoying to a point where I want to throw it out the window and break things in my room. Somehow... I don't think replacing the printer head will solve this problem, but I'll try it first.