Canon imagePROGRAF PRO-300 13" Photographic Inkjet Printer - Manual (Page 534)

Forgot Administrator Password of Printer
Initialize the printer settings.
On the HOME screen, select Various settings > Printer settings > Reset settings > Reset all and then
select Yes , restore to default administrator password.
Reset settings
After initializing the printer settings, redo setup.
Click here and redo setup.
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