I'm a new poster here at XDA , and I've gotten myself into a bit of a predicament. If there are any rules that I happened to skim over that are broken, please let me know! I have performed a search of my issue, but no solution has been procured from what I can tell.
For three days now, I've been trying to fix my phone. Stats below:
Model: SGH-I337 (AT&T Galaxy S4)
Build Number: JSS15J.I337UCUEMK2
OS: 4.3 (JB)
I believe that's all that needs to be listed, I'll be able to provide more information upon request if necessary.
I'll try to shorten my story to the key elements: Less than a week ago I tried to root, unlock, and flash a custom ROM to my S4 to no avail. I completed the rooting successfully and I believe I may have bypassed unlocking it via LOKI, but the ROM did not install. Since that failed, I've been trying for three days to completely restore my phone to stock and just deal with Samsung's TouchWiz UI. I can flash (through ODIN) my phone to stock 4.3 and everything is fine except for a lack of WiFi and Data. This is where my conundrum comes in to play.
Knox seems to display a message stating "The device has detected an application attempting to perform actions that are not permitted. These actions have been blocked. It is recommended that you restart your device." anytime that I attempt to turn WiFi on. The widget and the setting in options will attempt to turn on for a split second and turn off prior to displaying this security message. It's as if Knox believes my WiFi is attempting to access parts of my phone that are restricted. My data is able to be turned on in the settings, but no 3g/4g is ever utilized. I figured an update off of 4.3 would help remedy this issue, but I can't seem to update my phone through any other means (ODIN, Kies, no OTA due to no WiFi/Data, etc.).
I've run out of different combinations of the keywords about my problem to search for in Google and any question about my problem was asked approximately April-October 2013, not answered, and not many more similar questions have risen since then.. which leads me to believe that this fix should be relatively easy.
On an S3 forum thread (I know, different device) I read that there could be corruption of my Nandroid system, but I'm not even sure what that entails. The user answering implied that the phone was done for. Again, though, this was a separate thread for another user about a Galaxy S3.
Well, apologies for the wall of text, folks. If you are willing to assist me, I would very much appreciate it. Thank you very much for reading my issue and I hope assistance can be organized.