Follow these step:
Step 1
Open iTunes then connect your iPhone into your Win or Mac

Step 2
Press the Home button and the Sleep/Wake button at the same time. While you doing this, the screen goes black then release the Sleep/Wake button, but still continue hold the Home button.
Step 3
While holding the Home button, the iTunes pops up the message telling you that iPhone in recovery mode.

and the screen will look like this

Read more...
Step 1
Open iTunes then connect your iPhone into your Win or Mac

Step 2
Press the Home button and the Sleep/Wake button at the same time. While you doing this, the screen goes black then release the Sleep/Wake button, but still continue hold the Home button.
Step 3
While holding the Home button, the iTunes pops up the message telling you that iPhone in recovery mode.

and the screen will look like this
