Huawei Ascend Y200 hard reset using buttons
1. Turn off your Android Huawei Y200 U8655 phone or pull out battery and reinsert is after a fews seconds.2. Press and hold both Volume UP + POWER buttons for about 15 sec. until Andorid recovery menu comes up.
3. Select Factory reset /wipe data. (scroll down with VOL down.)
4. Select with power.
5. Scroll down to Yes -- delete all user data. Press power to confirm.
After all is done press power to reboot system now.
After data wipe has completed you are done. reset Huawei U8655 done.
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If your phone is responding to screen input, then open Settings from the Applications menu. Tap Backup & reset > Factory data reset; click Reset phone and then Erase everything to format your phone.