Canon equipped its Pixma MP190 printer to alert users when the machine has experienced an operational error. An "E6" means that ink has run out. Cannon also programmed the printer to cease functioning. This is a safety-net of sorts so that you don't experience poor print quality. It also aims to prevent hardware damage and mechanical failure. In the case of the E6, your active print jobs might also stop dead in their tracks. If this happens, you can temporarily continue using the Pixma MP190 to finish up your current activities.
Press the "Stop/Reset" button on the printer for at least five seconds to finish your interrupted print job(s).
Obtain new and fully-filled ink cartridges from a printer supply retailer.
Lift the cover, which is also the area where the printer scans documents. Remove the depleted ink cartridges. Insert new cartridges, following manufacturer instructions.
Most modern printers connect and rely on computer connections. Alternatively, use tools and utilities in the Microsoft Windows or Apple Mac OS X operating systems to troubleshoot and read ink levels in the Canon Pixma MP190 printer.
Bypassing the E6 error message will disable detection of remaining ink levels. Use caution when working with electrical appliances and machinery. Where possible, unplug the device before attempting to maintain and troubleshoot its internal and external components.