Printer message is: used ink

The waste ink tank on Canon printers is the ink absorber which holds the ink used during Print Head Cleaning process. When the error message indicates that it is nearly full, Canon indicates that the printer should be taken to the nearest Canon service center to replace the absorber. There is no supported "do it yourself" replacement for this piece of the printer. As per Canon:

This printer has an ink absorber that takes in ink during the printing and print head cleaning processes. The cleaning process is necessary in order to keep the print head nozzles from becoming clogged. Over the life of the printer, the amount of ink that the ink absorber has absorbed is calculated by the printer. Eventually, after substantial use, the printer will enter an error condition when the ink absorber is nearly full. At this point, printing is still possible. Press the <OK> button to cancel the error. You will still be able to print for a short period. To protect the printer from damage, you will not be able to print at all once the ink absorber is full.

Canon recommends having the printer serviced before the absorber becomes full. We are aware that there are many "do-it-yourself" Web sites that offer instructions for making this repair. Replacing the ink absorber is a complicated and potentially messy procedure. Even if the ink absorber is successfully changed, the ink absorber counter must be reset. Be aware that if you attempt this procedure, it is at your own risk.

If you feel your product might require service, Canon has excellent service options, and we are eager to provide any assistance you may need. Click the link below to locate an authorized service facility and obtain further instructions.

So, to answer your direct question directly, if the message said "nearly full", you can press OK and continue to print for a short time. If it indicated it is full the printer will not function until Canon services the machine and resets the printer.

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