How to unroot your Epic Touch 4G and get it back to stock.
*This method saves user-data and does NOT format it.*
1. Put your device into Download Mode leaving it unplugged from PC. With the phone off, press and hold volume down and power to power the device on holding until it powers on. You will get a warning about custom OS issues, just press volume up to bypass this. Your device screen should look like this image below.
2. Run EpicTouch4G_Toolkit.exe click Unroot tab and then click "Back to Stock Rooted". This will launch the Odin OneClick root method. After it starts, plug your phone into your PC, letting the drivers install completely. If all is well Odin should should have a yellow box with 0:[COM#] and the screen will look like below.
Note: the COM# does not matter as long as its yellow and has one.
3. Click Start, let it do it's work(this could take several minutes to do, so
don't get scared, let it work) and you should get a PASS! message in Odin letting you things went alright. If so your phone should reboot and it will be back at stock rooted state Now we must remove the root files.
4. Once your phone has rebooted and USB Debugging is enabled go ahead and click the Unroot tab and click "Unroot My Epic Touch 4G". Let it remove the root files, this shouldn't take to long and your device will reboot when it's done. Your device is now fully unrooted and back to stock condition!