Well, whomever gave you the phone loaded up a leaked version of Gingerbread. Not a big deal, but it does put you into the self-service line whether you wanted to be there or not

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First, it would be good to know a little more detail about what you are actually running right now. Hit MENU-SETTINGS-ABOUT PHONE and list back what is listed for BUILD NUMBER and BASEBAND VERSION. That will let us know better what your starting point is.
Meanwhile, back at the Hall of Justice, go here-
[ROM][2.3.4][Gingerbread KH3]♦ Pinnacle 1.3 ♦ 09/24 - xda-developers
Download the 1.2 full ROM and the 1.3 update. Copy both to your phone. Also, on the original link I sent you, under the list of all the kernels and ROMs is a link for Odin. Get that too.
The top sticky in this forum is on rooting and ROMs and whatnot, good for reference... but you will need to brush up on a couple basics. There are button codes to push to get your phone into special service menus. these modes are Download Mode and Recovery Mode. There is no risk in simply getting to these modes, and before we proceed, you should practice it a few times each.
Recovery Mode- Start with the phone OFF. Press-hold the middle of the volume rocker so both VOLUP and VOLDWN are depressed. Press the power button, so you are holding all three down at the same time, until the screen lights up and let go of everything. You should boot to a screen with blue text on it. Use the volume rocker to move the selector and the power button to actually select. Choose to reboot or pull the battery. Do it again a few times until you can do it without fail. CWM stands for Clockwork Mod Recovery. It replaces the stock Recovery Mode with one that lets you do cool stuff.
- Depending on what your phone has loaded, you may already have CWM which makes this easier. Take note of the version across the top of Recovery Mode and include that in your reply. It may save a step.
Download Mode- Download mode is like the 10lb sledgehammer of fixes. You should only need to get here once in a while, and it is correspondingly more annoying to get to. For this one, you need a computer and when you actually want to do something instead of just test if you can get here, you will need Odin (I mentioned it above) running on a Windows computer and a USB cable.
Power the phone OFF.
Remove the battery.
Open Odin on the PC and connect the cord to the phone (already connected to the PC)
Press-hold the volume rocker so both VOLUP and VOLDWN are depressed
While holding those buttons in, stick in the battery. (this can take practice)
You should get a yellow triangle digger bot on the phone screen, and Odin should show that it can see the phone. Pull the battery to shut off, and try it again a few times for familiarity. So long as you do not run Odin while doing this, you are in no risk.
Depending on what you have, will dictate the next steps
