I have an Android Motorola Xoom and I rooted It. Then, I decided to unroot it and update it, since you cannot update when rooted. But when I started to update it (the update is called HLK75F), it showed a green character with a triangle and a exclamation mark in it. Then, I have to reboot it and I get no update. What is causing this to happen and why is it happening and how to I fix this? My Android version is currently 3.2.2. Somebody please help me.