At this rate, the other print cartridge will have dried up.(I always try and use my printer on a weekly basis, even if its only a test page) Brian
If you are desperate to scan and want to take a risk then there appears to be a service mode to over-ride the error code. This may or may not work or screw up your printer.http://www.fixya.com/support/t1781424-canon_mp145_stop_error_e5_use_scanner
Not sure if this will work for your scanner, but can you get into the maintainance menu and then tell it to work from only the cartridge you have in the machine. Sorry I have just read through the thread and already forgotten which cartridge you are missing I have a different cannon and can get it to run from just one cartrdige if needed.Pebs