Press and hold the buttons simultaneously.
If you can access the menu, this is the safest way to wipe your data: Go to the from your home screen. Select Settings > Privacy . Tap Factory data reset > Reset phone . Enter your password if prompted and tap Erase everything . Method 2: Using Hardware Keys (If Locked) Sony Ericsson Xperia Mk16I Hard Reset
A hard reset will permanently delete all internal data. Ensure you have backed up any important files before proceeding. Hard Reset SONY ERICSSON Xperia Pro MK16i Press and hold the buttons simultaneously
Select and then "reboot system now" once finished. Feature Idea: "Quick-Key Cleanse" use this manual method: the device.
If your phone is frozen or locked by a pattern/PIN, use this manual method: the device.