Stock 4.2.1, boot loader still locked.

On 4.2 I was able to run an adb backup using the nexus root kit. I did the OTA update to 4.2.1 and now I'm unable to, here's what happens.

After initiating the back up, the device reboots and at the last step there's an on screen prompt to deny or allow the backup to run. Similarly when installing an apk there's a prompt to cancel or install.

On both the adb backup and apk install i'm able to select the cancel button on the left. When pressing the install/backup button on the right it does nothing. The button doesn't even highlight when I press on it.

Does anyone have a clue as to what's going on?

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