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If you cannot boot try wiping the cache portion deleting all temporary data and not touching any apps you installed or data you saved. To do it ...
Step 1: power your Bionic down
Step 2: hold volume up, down, and power simultaneously
Step 3: use the volume down to navigate to "recovery" use volume up to select
Step 4: you will get a screen with a triangle with an exclamation point, next to an Android. Press volume up and down simultaneously
Step 5: use the volume rocker to navigate to "wipe cache partition" and use the power button to select.
Step 6: after it has finished, use the volume rocker to navigate to "reboot system now" and use the power button to select.
... Thom