Using the wrong version of the service tool or an unauthorized copy can permanently lock your printer's Service Mode

Using the tool is relatively simple, but it requires your printer to be in . Part 1: Entering Service Mode Turn off your printer (do not unplug it).

Search for "Canon Service Tool ST 5510 free download" on trusted printer forums or dedicated support sites. Download the .zip or .exe file. Create a folder on your desktop and extract the contents.