So I tried to install custom Rom, and I bricked My Samsung Galaxy S4, running on 4.3. I tried to use ODIN, but my device is not detected on there.
On the top left hand of my device says "Secure fail: Kernel" And the screen reads : "System software not authorized by ATT has been found on your phone"
My device is an ATT Samsung Galaxy s4 I337. Running 4.3.