Hello Mark5,
If you are getting blue lines during copies, it could be caused by a problem with the hardware or the toner cartridges. In this situation, I would suggest reseating the toner cartridges and check for any obstructions. While the toner is out of the printer, you can give the toner a gentle shake to make sure the toner is evenly distributed. You can also check the toner for any leaks/cracks. If reseating the toner or replacing the cartridges does not resolve the issue, it looks like the printer needs service. You can log into your MyCanon account or contact support at 1-800-652-2666 to check your service options.
