For that, you should carefully follow these steps:
1. Go to the Control panel ad open the ‘Devices and Printer’ option.
2. Right-click the printer you want to clear memory from
3. Click on the ‘See What’s Printing’ option.
4. In the printer menu, click on the ‘Cancel All Documents’ option.
5. Choose ‘Yes’ the list should clear’ option.
Once you complete the above-mentioned steps, you should quickly reboot your computer system or factory reset Canon printer. Doing so will clear out all the memory that is full of printing jobs.