This guide has been compiled for the porpose of un-rooting your phone in case you're thinking of selling it, or returning it under warranty due to hardware failure.
This guide is intended for those who used the Advanced Ace Hack Kit to root their phone.
Never having done this myself, I'm unsure as to potential errors or what the actual process is. If you have an alternative method, or have more details on the process, drop me a PM and I can add them to the guide.
Please note that the usual warnings/disclaimers apply (click show)
Quick note / disclaimer: as always, you are ultimately responsible for any root-related activities on your phone.
You should understand not only the benefits of rooting, but also any possible consequences (voided warranty, boot-loops, bricking, etc.) that might occur as a result of your root-related actions.
AndroidForums.com / Phandroid.com, its owner, and staff are not liable for any root actions you might undertake as a result of information used from this site.
Reading, researching, understanding, and carefully following the published steps and instructions can go a long way towards helping to make your rooting efforts a successful one.
As I have said above, if you used the AAHK to root your phone, then the easiest way to unroot is by using the kit again.
By following on screen prompts, you would select "O" for Options Menu and then "S" for S-On and return to Stock.
You then choose one of three Stock firmware RUU's to put on your phone.
For the majority of people it should be "2" - "Flash Gingerbread WWE RUU", which is unbranded (the AAHK may have to download the RUU, which could take some time).
The Hack Kit would then run the RUU.
Your phone will now be back to unbranded stock Gingerbread.
If you are wanting to bring the phone bang up to date, then you would need to run the latest RUU currently Sense 3.0 (the 4th from bottom in the linked list - build 3.12.405.1).
Your phone will now be back to unbranded stock Gingerbread, with Sense 3.0
Please note that ALL questions relating to the Hack Kit should be addressed in the manual (if you are following the guide to unroot, you already know this, as you used the Hack Kit to root in the first place!)