[Q] Rooted Sprint S3 doesn't move past S3 logo on boot

[rxenergy]

I was trying to install a theme with ROM Toolbox when the phone froze on me. I tried to reboot it but it wouldn't go past Galaxy S III logo, or I just don't see it as it seems like the phone stays on, but the screen doesn't come on. I was able to boot into ClockworkMod Recovery screen and did a factory reset hoping that would help, but it didn't.
Tried searching the forum looking for an answer, but sadly all I found were few on other devices. Please help a n00b!

 

[rxenergy]

ok, did some research and will be trying qbking77's method to unroot/unbrick this one. hopefully that'll work.

 

[Soundtrack to Chaos]

Just as a precaution, never, under any circumstances allow rom toolbox to reboot your phone at any time, regardless of if you just installed a theme or a font

Always exit the app and manually reboot

I had a simular issue, but was able to fix it by wiping and then flashing again

My name is Soundtrack to Chaos, and I have a fetish for external chargers, big batteries, power outlets and extension cords... I need help

 

[meyerweb#CB]

If you can get into CWM recovery, you don't need to revert to unrooted. Just flash a known good ROM, like the stock MD4 (assuming you're on Sprint) found in post #2, here: http://forums.androidcentral.com/sprint-galaxy-s-iii/272331-your-way-update-md4.html

Do you still have the original ROM you flashed, before trying to theme it, on your phone? If so, flash that one again. If not, you'll need a way to get a new file onto your phone. An external card reader and micro-SD to SD adapter would let you do that.