How to reboot your Android device in recovery mode.

You have to press one combination of keys for rebooting device in the recovery mode. Combination of keys is different for each brand. Major ones are as follows.

There are various hard reset Android phone key combinations depending upon the type and version of your phone.

However, any of the below mentioned key combinations will definitely work out on your phone to start hard reset mode. 

Combination 1 - Volume Up + Camera button. 

Combination 2 - Volume Down + Power button. 

Combination 3 - Volume Up + Power button. 

Combination 4 - Volume Up + Home + Power button. 

Combination 5 - Volume Down + Volume Up + Power button. 

Combination 6 - Home + Camera button. 

Combination 7 - Home + Power button 

Most of the devices will most likely use the similar key combinations and in case any of the above mentioned combinations don't work, please check the manual or support page.

Warnings 

1. Resetting your phone must be the last option so you must spend time to analyze the real problem with your device. It may be android system, any app or your SD card.
2. If you notice excess battery drain than normal, you may opt to reset your phone. Check your battery life by Menu > Settings > About Phone > Battery Use.
3. If you feel your apps are the reason, you should manually create backup of your apps and consider the rest which are troublesome on case to case basis. But it takes time. Letting Google cloud do the restore is quicker and less painful.
4. Your battery should be atleast 50% charged. It will allow uninterrupted hard reset.
5. Before hard reset, make sure your data is backed up.

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