First step to Install Firmware 

1. Sky Offline Flash Tool V1 Sky Flash Tool 2014 B2
2. Sky Offline Flash Tool V2 Sky Offline ROM Flasher
3. Sky Vega All USB  Driver Install on Computer

How To Flash Sky Vega IM A820L 

1. Download Offline Flash Tool And Drivers.
2. Install Offline Flash Tool And Sky Vega Drives
3. Update Your Microsoft Internet Explorer
4. Put Device in SW Upgrade Mode
5. Connect Device With PC Via USB Cable
6. Check Installed Drivers in devices manager
7. Press Firmware Upgrade Icon in Internet Explorer
8. your phone start flashing, and your phone will be flashed about 5 to 10 minutes after flash phone automatically restart when phone reboot unplug the cable now you have successfully flashed your phone.
9. After flashing process, starts, it might take up to 5-10 minutes. So, keep patience and wait.
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