If you have forgotten the password for your encrypted iTunes backup, then provided your device is running iOS 11 or newer, you can reset it by following these instructions:
1. On your device, go to Settings > General > Reset.
2. Tap Reset All Settings and enter your passcode.
3. Follow the steps to reset your settings. This won’t remove any user data from your device, but it will reset settings like display brightness, Home screen layout, and wallpaper. It also removes your encrypted backup password.
4. Connect your device to iTunes again. Encryption will now be turned off and you can click Back Up Now to create a new unencrypted backup to scan with Certo iPhone.