If you change a new password and then forget it suddenly, it would be a little hard for you to deal with it. iOS Restoring could remove your data. However, 3uTools can’t only jailbreak and flash iOS devices, but also provide a variety of useful advanced features, for example, retrieving the device’s password. You can tap “Jailbreak→Advanced” to find it. But the tool can only support iPhone3GS and iPhone 4 running the system lower than iOS7.0, and retrieve the 4-bit passwords. Anyway, please do what 3uTools reminds.
Step 1. Connect your iPhone to the computer via the original Apple USB cable, and then start 3uTools.
Step 2. Please ensure your iPhone in DFU Mode. As to the steps to enter DFU mode, you can do acccording to the tool's reminders. Then Tap Flash Jailbreak→Advanced→Retrieve device’s password.
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If you want to view more details, please click here: http://www.3u.com/tutorial/articles/how ... ng-3utools