Summary: I have the MP610 and I can override the no go when an ink tank is empty by pressing the "ok" button in the middle of the wheel on the actual printer. That overrides that message and it even prints after doing that. Give it a go on your MP500.
Summary: The Canon PG-30 Black Ink Cartridge is a great replacement to my original cartridge. I occasionally print documents using a Canon Pixma MP210. When it was time to replenish my ink, J&R had the right product at great price.
Pros: Clean Replacement, Easy To Install, Sharp Tones & Colors