昨晚在DELL官网翻到的，Venue 7 or Venue 8 tablet may become unresponsive during Android 4.4.2 (KitKat) operating system upgrade
Dell has received reports of Venue 7 or Venue 8 tablets locking up during the Android 4.4.2 (KitKat) operating system upgrade.Recovery stepsNOTE: Anytime you attempt an operating system upgrade, ensure that the system battery has at least an 80% charge.
Follow these steps to recover your system:
Press and hold the power button until the tablet completely powers off
With AC power connected to the tablet, Press Volume Down and the Power Button(Volume Down + Power) at the same time.
Select RECOVERY
When you see the Android Robot Icon, Press Volume Up and the Power Key (Volume up + Power) at the same time
Select "Wipe Data/Factory Reset" then select "Yes - Delete all user data to factory reset"
After factory reset completes, select "reboot system now" to reboot system.
System should recover and boot into the current update version of Android OS.If the tablet fails to recover, contact Dell technical support for service on the tablet.
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