This method will upgrade your phone os, and give you root, but warning it does delete the entire contents of your phone, but it will leave your sdcard intact, so make sure you save your stuff to the sdcard before you do this.

Right now there are two problems with upgrading from froyo to gingerbread on an epic 4g

1) clockworkmod breaks the stock gingerbread upgrade

2) there is no oneclick root on gingerbread

The easiest way to do the upgrade is first go back to factory froyo — only do this step if you already have root and clockwork and the standard system update to gingerbread fails.  Download odin and the tar files outlined here:

Basically you download odin version 3, froyo, do a stock update to gingerbread, reboot download a boot program, load root, and you’re finished.

Get odin here:

Boot your phone with the power & 1 key held down.  When it gives you the yellow download sign, plug it in.

Grab these two files (one is a pit the other the pda)…b-REL.tar.html…n_20100512.pit

Restart.  Now you are in stock Froyo and the Gingerbread update will work.  Next to root the phone you need two files, ACSRecovery and from here

The files are

Plug in your phone and tell it you want to go into the usb mode where you can transfer files to the sdcard, and put the on your phone, and the file on your computer.  Power off the phone and once again go into download mode with power key and “1” and this time choose ACSRecovery to add to your machine, but tell it NOT to reboot.

Now normally in a one click root program, the script disables the boot script of the stock phone which checks for updates and overwrites clockworkmod or ACSRecovory, but since you are doing it by hand from a stock phone, you have to know that the first time this phone boots up it will delete that copy of ACSRecovery.  So, after you have used odin to put acsrecovery on your phone with power & 1 key  (but not camera — it’s volume up key on the epic touch by the way) and clicking oden3, PDA and start, make sure you reboot with

volume down – power – camera

. . . until the keys light up on the screen.  If you miss time this you’ll have to go back to odin and reload ACSRecovery.  There is a file under /etc on the phone that checks to see if the phone isn’t up to date, and if that script runs it’ll overwrite acsrecovery, but it’s ok, we only need to use it once.

From ACSRecovery go to advanced, and select the file we put on the phone earlier, then reboot.

Then you’ll have a stock epic 4g phone rooted, running gingerbread, but no clockworkmod, or ACSRecovery, just the stock boot diag, which is what I wanted in the first place.

I think most of the methods out there are for people that want their own kernels, I just wanted the stock kernel and root.