Originally Posted by mikeytusa
I was running 5.0.1, rooted and decrypted. Followed WUG's instructions for flashing 5.1 and once it installed I seem to be stuck in the "Optimizing app..." part. Once it finishes optimizing my apps, it reboots and does it all over again. What should I do?
Same thing happened to me. Here's what I did.
1. Press and hold power, volume up, and volume down. Keep holding them down until the phone boots into bootloader mode.
2. Go back to the toolkit and click the radio button labeled "Soft bricked/bootloop"
3. Click "Flash stock plus unroot"
4. Check all the boxes under "Settings", including "Post-flash factory reset" then click OK.
5. Follow the toolkit instructions from there.
This got me out of the bootloop, successfully installed 5.1, and kept all my apps and settings. Good luck.