How do you reset lost vizio parental code?

To reset a lost Vizio parental control code, you typically need to perform a factory reset on the TV. This can be done by pressing the "Menu" button on the remote, navigating to "System," selecting "Reset & Admin," and then choosing "Reset TV to Factory Defaults." Note that this will erase all settings and preferences, so you'll need to set up the TV again afterward. If you have a specific model, consult the user manual for detailed instructions.