My Canon MP530 just stopped !
It said it needed a cartridge to be changed.
I took it out and .... it was EMPTY.
I used to have an Epson printer. Well several actually.
When it informed me that it was out of ink, I would take out the cartridge a shake it. The sloshing sound didn't sound empty.
I am more than a little ticked at Epson for this.
I couldn't be happier with the Canon.