Originally Posted by Sinistertensai
try another superuser then. and odd it's repeatedly asking. you running any mods, tweaks, xposed?
There are no modifications. I simply flash the RUU 4.13.651.4. Flash TWRP. Problem occurs. In fact, I don't even have to have SuperSU installed. I know it is trying to do something because it keeps cycling through saying "Reading SIM card..." and there is an icon on the top left that has a picture of a SIM card with an exclamation point on it.