It is on page 11 of the User guide
It is on the Xerox support site.
You can get the error on a perfectly good new cartridge if it is the wrong one (Metered vs sold, or even region coding, which means like bought the printer in the USA and bought the toner in Europe)
No where in the user guide can I find what a solid red light means.
Cart is good
No paper jam
Unplugged to reset
Nothing works, Get no error messages
Suggestions on what the problem is