Switched back to Android and cant get root

Ok, so I have a Galaxy S3 SGH-I747 running 4.3 android on AT&T. I installed Keis to ensure that my Mac had the proper drivers and could recognize my phone. I am running Mac OSX 10.9.1.

I have tried several different methods to root to no avail.

I tried the CASUAL jar root method. Went through the process but installs a version of SuperSU that does not contain binaries and the knox blocks.

Then I tried flashing the root method that isnt supposed to trip flash counter by mrRobinson.

I tried a couple of other methods using Heimdall but could not get Heimdall to allow me to flash anything. None of the files I extracted were available to select.

Really frustrated at this point. I switched back to Android just to tinker with Android OS. Help!!!!!

Thanks for the response. I got the phone from a buddy so I'm betting he did the OTA update.

Are there any options for rooting after the 4.3 update?

Sent from my SAMSUNG-SGH-I747 using xda app-developers app

Not concerned about Warranty. The challenge I am having is using Hiemdall instead of Odin since I am on a mac. I can't seem to fgiure out how to get hiemdall to flash anything.

Thanks again.