Follow this guide to install SmartSwitch on your PC.
Step 1: Prepare Your Phone

To get started, make sure your phone is at least halfway charged, because you don't want to lose power in the middle of an update. Beyond that, have your phone powered on and booted up, then connect it to your computer with a USB data cable.Step 2: Install Smart Switch for Mac or PC

Next, from your PC or Mac, click one of the following links to download the Smart Switch desktop program:
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Once the file has finished downloading, go ahead and launch it, then follow the prompts to get Smart Switch installed on your computer.
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Step 3: Back Up Your Existing Data

Once installed, Smart Switch should automatically recognize your device type and download all corresponding drivers without any further interaction from you. This means that as soon as you finish with the setup wizard, you're ready to use Smart Switch.One of the first things you should do is create a backup of your existing firmware, data, and apps. To do that, just click the "Backup" button near the bottom of the screen, then wait about 10 minutes for the process to complete. Should you ever need to restore this backup, the process is equally simple—just click the "Restore" button, then select the backup you made, and Smart Switch will handle the rest.
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Step 4: Update Your Firmware

If there is an available firmware update for your device, Smart Switch will inform you of this with a message near the top of the screen. Just click the "Update" button directly to the right of this message to begin the update process.
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From here, you'll be asked to confirm your choice, so click "Update" again on the subsequent popup.
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Next up, you'll get a message detailing the update process.
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After clicking "OK" on the previous message, Smart Switch will start the process of updating your phone's firmware. While this is happening, do not touch or interact with your phone at all.
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Depending on your computer, the update process may take up to 30 minutes, but when it's done, you'll get a confirmation dialog. As it says, you should disconnect and reconnect the USB cable at this time.
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Your phone will take longer than normal to boot back up, but once it does, you'll be running the latest version of Android. After your phone has finished booting, it's safe to disconnect the USB cable entirely.Source: [ Login above or register to see download links. ]