MIUI6 ROM V 5.6.11
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There is no need to do it again if you’ve already downloaded
the latest ROM file.
Connect your device to the Windows PC/laptop via a micro USB
cable, and copy the ROM file
downloaded in Step 1 into the folder
‘downloaded_rom’ in the internal storage of your device.
Launch ‘Updater' app on your device:
MIUI 6:Click the ‘…’ icon at the top-right corner, select ‘Choose
update package’, and choose the ROM file you’ve put in ‘downloaded_rom’ in Step
2.
MIUI V5:Press the Menu button, select ‘Choose update package’, and
choose the ROM file you’ve put in ‘downloaded_rom’ in Step 2.
After choosing the right ROM file, your device will begin
upgrading. Your device should automatically boot to the new version when the
update is completed.