Celkon A66 hard reset using buttons

1. Turn your Celokon phone off.
2. Press and hold both Volume DOWN and POWER ON the phone.
3. After your phone vibrates release only power button but keep pressing the volume buttons until recovery menu apperars on the screen.
3. Highlight Wipe Data/Factory Reset with Volume down button.
4. Press Power to confirm.
5. Reboot system after recovery hard reset.

After all is done press power to reboot system now.

After data wipe has completed you are done. reset Celkon A66 Android phone done.

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.

Restoring Celkon A66 Factory Data

If you reset your phone to its factory settings, all of your personal data stored on the phone, including information about your Google account, any other accounts that you
have configured, your system and application settings, and any applications you have installed will be erased. Resetting the phone does not erase any system updates you
have downloaded. Using the check box provided, you can also select to erase all the data stored on your SD card or on the phone’s internal SD card, which includes files
that you have downloaded or copied there, such as music or photos.
1. On the Settings screen, touch Backup and Reset for Factory data reset.
2. When prompted, touch Reset phone, and then touch Erase everything. The mobile phone resets the settings to the original factory settings, and then restarts.