So for my HTC One M9, I recently updated it to the 6.0 OS. It updated just fine, but it took a couple of hours to fully restart because it was stuck in the optimizing apps screen and would continuously reboot and go back to that screen. It eventually started working again, but I got a notification that said the lock screen has to update. I then pressed update now, but it went back into the same loop as mentioned earlier. And now, almost 48 hours later, it still hasn't gotten out of that loop. Any help would be appreciated.
Let’s see how we can get your HTC One M9 device out of this endless rebooting loop. I am happy to help.
First, let’s try restarting the device by following these steps: http://vz.to/1L9oKAp. If that doesn’t work, please remove the Memory Card: http://vz.to/20TfYbT and then attempt powering up the device. Let me know if the device powers up with the Memory Card removed.
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