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xolo a500 hard reset
Power off the phone
volume down + power switch
In the recovery menu select wipe
 data factory reset with Volume
button. Press power to confirm.
After hard reset completed,
select reeboot system now! 
All data will be lost!

Hard Reset:

    Press and hold Volume UP + Home + Power Key Until Samsung logo Appear
    Now you see android recovery logo
    Now select Wipe data/factory reset and press power key to confirm
    Now select Yes -- Delete all user data and press power key to confirm
    Now reboot device
    hard reset done

Hard Reset by code:

    Enter dial no *2767*3855#
    Now your handset show Factory Format
    Wait for restart handset
    hard reset done

    How To Hard Reset Your Samsung Galaxy Tab 2

    Switch Off Your Mobile Phone
    Take Out Your Sim card And Memory
    Press And Hold Both Volume Keys +Power Button
    When You Got Android Recovery Menu . Release  All Keys
    Scroll Selection To Factory reset /wipe data Using Volume Key
    Confirm Selection Using Power Key
    Then Select  Yes -- delete all user data And Confirm
     Wait Some Seconds. Then Select Reboot System Now Option And Confirm
    Now Your Phone Will Restarted. After Completing The Hard Reset Process
    Done ! Enjoy

Before you buy a new cell phone or new tablet, please try the following procedure to repair your device. First charge your battery, backup your important data if possible and in most cases take out SIM and SD card. It is impossible to recover your data after doing a hard reset, so online backup is always important. For all of your data, a backup should be done on an external device, hard drive, raid system or media.

Alcatel OT-985 Android hard reset
If your One Touch 985 Andorid mobile phone is dead, can’t power on
- Make sure your battery is not completely used up or damaged.
- Remove your battery, remove your SIM card then power it on again.
- Check the battery power level, charge for at least 20 minutes before doing a hard reset.
Alcatel OneTouch 985 Android hard reset using buttons
When you are unable to power on your phone, there is a way to perform a factory data reset by using hardware keys.
Turn off your phone. Hold down Volume down key and press Power key at same time until the screen lights up and then press Home key. Be sure to backup all your data before resetting your phone. All data will be lost!  Use ALCATEL Android Manager to manage your data.

ALL User phone data: contacts, photos, messages and files, downloaded applications like Java games will be lost permanently.

Factory data reset OneTouch 985 Andorid cell phone
Erase all of your personal data from internal phone storage, including information about your Google Account, any other accounts, your system and application settings, and any downloaded applications. Resetting the
phone does not erase any system software updates you’ve downloaded or any files on your microSD card, such as music or photos.

or

Go to Settings >Privacy > Factory Data reset > Reset phone > Erase everything.
or
Use User Data Format and the One Touch Upgrade tool to perform phone formatting or software upgrading, (to reset User Data format, hold down
Volume up/down key while simultaneously pressing the Power key).
ALL User phone data: contacts, photos, messages and files, downloaded applications like APK games will be lost permanently. It is strongly advised
to fully backup the phone data and profile via Android Manager before doing formatting and upgrading
How to soft reset Alcatel OneTouch 985?
Restart your cellphone by pressing and holding the Power key.
Remove the battery and re-insert it, then restart the phone.
Connect your phone. 

 HTC Dream- hard reset
Before you buy a new cell phone or new tablet, please try the following procedure to repair your device. First charge your battery, backup your important data if possible and in most cases take out SIM and SD card. It is impossible to recover your data after doing a hard reset, so online backup is always important. For all of your data, a backup should be done on an external device, hard drive, raid system or media.

HTC Dream Soft reset

Soft reset
A soft reset clears the device memory and closes running applications. Perform a soft reset when your device hangs or freezes, is running slower than normal, or an application is not performing properly. If a soft reset is performed when applications are running, unsaved information will be lost.
To perform a soft reset
1. Remove the back cover.
2. Remove the battery for a few seconds.
3. Re-install the battery, replace the back cover, then turn on the device

To remove the back cover
1. Make sure the device is turned off.
2. Hold the device sideways with the control buttons on the right.
3. Slide the screen panel up to reveal the keyboard and the back cover release tab.
4. Gently push down the release tab with your finger until the back cover disengages from the device.
5. Pull the back cover out then set it aside.
HTC Dream hard reset
HTC Dream hard reset
HTC Dream Android hard reset

1. The device must be powered OFF to Dream hard reset.
Note: If the device is not responsive and does not turn off, remove the battery and re-insert it.
2. Press and hold the Home button and the Power button at the same time.
3. Keep holding Home and Power together for at least 25 seconds, even if the "Startup" screen appears.
4. Release the keys when you see a black screen with a warning sign.
5. Slide the keyboard open.
6. As a shortcut, press ALT+W to factory reset the device. If this does not work, continue with the below steps.
7. Press ALT+L.
8. Press Alt+W for wipe data/factory reset.
9. Press the Home + Back key.
Note: You can also remove the battery and re-insert it.


Factory reset
Performing a factory data reset deletes all data, including downloaded applications, and resets the device back to its initial state—the state before you turned on the device for the first time.
Important Make sure to back up important data you have on the device before you perform a factory data reset.
To perform a factory reset
1. Press HOME > MENU, then touch Settings.
2. Scroll down the screen, then touch SD card & phone storage.
3. Navigate to the Internal phone storage section, then touch Factory data reset.
4. When prompted, touch Reset phone. The phone resets and displays the Home screen.

How to Soft Reset HTC Dream

A soft reset htc dream clears the device memory and closes running applications. Perform a soft reset when your device hangs or freezes, is running slower than normal, or an application is not performing properly. If a soft reset is performed when applications are running, unsaved information will be lost.

To perform a soft reset

1. Remove the back cover.
2. Remove the battery for a few seconds.
3. Re-install the battery, replace the back cover, then turn on the device

To remove the back cover
1. Make sure the device is turned off.
2. Hold the device sideways with the control buttons on the right.
3. Slide the screen panel up to reveal the keyboard and the back cover release tab.
4. Gently push down the release tab with your finger until the back cover disengages from the device.
5. Pull the back cover out then set it aside.

Reset to factory settings
Nokia N96 Hard Reset, Nokia N96 Master Reset Nokia N96 reset
To perform a master reset or hard reset on your Nokia N96 you will need to:
dial *#7780# or *#7370#
enter your security code (default is 12345)

LG GW620 [Eve] Hard Reset

To do a hard reset or data reset in LG GW620 aka EVE
Enter using Dial pad
3845#*620#
From menu select factory reset or whatever you want.

We have our own reasons why we hard reset our device. Maybe we want to delete all the files and restore the device to its original state. It could also be the device may be malfunctioning or so slow and it needs to be reset.

Restoring the default settings or factory reset your Sony Xperia Z2 will delete all your existing files. It is recommended to backup your important files on your computer before attempting to reset your device.

Use this method if your device is frozen or unable to solve by Factory Reset.

Hard Reset: