[EVO 4G General] shortydoggg:
Here is a quick guide on how to unroot the latest RUU 5.07. It seems that quite a few people are having trouble unrooting their device or running an official RUU while being on the latest update, or a ROM based on the latest update.

The problem is that HTC has fixed the bootloader (in particular Hboot 2.18) so that it will reject any PC36IMG.zip official software or RUU files that update previous operating systems on the phone (a S-ON phone). You would usually need a RUU (I'm calling both the PC3IMG.zip file and the RUU file an RUU) that is for your current operating system. If your phone is on the latest 5.07 update or a ROM that is based on the 5.07 update, then latest RUU that exist is for the Evo with RUU Supersonic 4.67. 5.07 never came out, done intentionally by HTC I believe. So none of the RUUs which exist today will work with the 5.07 update. The problem exist because the phone's misc partition is updated whenever you accept an update or run a RUU from HTC, or even flash a ROM. There are other cases as well. The only way to run an official RUU on a phone that is not currently S-OFF is either to downgrade the phone's misc partition, or to turn the phone S-OFF (which you will still have to flash the phone's misc partition to do).

What I've done is put together a quick guide for those who need (or just insist) on unrooting their Evo. It is brief and only for a PC (not a Mac). Hopefully, someone in the future can provide further details or make it Mac friendly or even more user friendly because I don't have a Mac, nor the time to spend to make this guide perfect. I have another phone too to deal with. Remember too, that everything is done at your own risk. So if something goes wrong, well you knew the risks.

For this guide I'm going to assume that you are on Hboot 2.18, the phone is S-ON, the bootloader is unlocked (UNLOCKED), and that the phone's ROM is currently rooted. If not, then this is not the right guide for you.

1. Download this zip file. It contains the necessary files that you will need.

https://dl.dropbox.com/u/38127313/sdk.zip

2. Plug your phone into your computer. Then go to Settings/Applications and uncheck Fastboot. Then goto Development and make sure that USB debugging is now checked. If you have a custom ROM, then the locations of these settings may be slightly different.

If you need the HTC drivers, then I have also included the drivers.exe file that you must run from your computer to install the "MyHtc" drivers that you must have under the computer's device manager when the phone is plug in.

3. Next, unzip the file to a folder, preferably sdk. Rename the "PC36IMG_SuperSonic_GB_Sprint_WWE_4.54.651.1_Radio_2.15.00.0808_NV_2.15_release_220182_signed" file to PC36IMG.zip (not PC36IMG.zip.zip). Place the phone into "Disk drive, then copy the PC36IMG.zip file to your sdcard. Afterwards, don't forget to change the phone back to "Charge only".

4. Next you will need to open a command prompt at the folder where you extracted the files. If you are not familiar or uncomfortable with adb commands, then I cannot help you here.

5. Type or copy the below commands exactly as they appear.

adb push flash_image /data/local <ENTER>

(This places the file on your phone in the /data/local directory).

adb push mtd-eng.img /data/local <ENTER>

(This places the file on your phone in the /data/local directory).

adb shell <ENTER>

(You should see either a dollar sign ($) or a pound sign (#) at your prompt, depending on your ROM. If you do not then something went wrong. And, No the phone will not brick if you should stop at this point).

su <ENTER>

(You might not need this command depending on your ROM, and also you should check to see if your phone is asking for superuser permissions. If everything went Ok, you should now see a pound (#) sign at your prompt. If you do not then something went wrong. And, No the phone will not brick if you should stop at this point).

cd /data/local <ENTER>

(You need to be in the directory where you put the flash_image and mtd-eng.img files).

chmod 755 flash_image <ENTER>

(flash_image needs to be assigned permissions).

./flash_image misc mtd-eng.img <ENTER>

(This is the most critical step here).

reboot bootloader <ENTER>

(I prefer this step, as it is much faster than pulling the battery and all that other stuff that people suggest).

The phone should now reboot directly into the bootloader. Also the phone will now be locked again (LOCKED OWW) regardless of its previous state. Next hit the power button. It will then take some time to read the PC36IMG.zip file. If everything went Ok, then it should ask you whether or not you want to accept the update, which means that your misc partition was successfully downgraded, and now you can successfully run the RUU.

EDIT: I have to re-upload the sdk.zip file, because the original one had a problem with the PC36IMG.zip file. It should be available shortly. The one I added does work this time; however, the phone may have to be updated in order to bring it back to the latest bootloader and update. It's not the latest RUU 4.67, but the second latest 4.54. I cannot believe that something was wrong with that file. Also, instead of the PC36IMG.zip file that I added, you could also use any other PC36IMG.zip file or a RUU.exe file from HTC. They should work as well. I would not recommend a RUU below Supersonic 3.70. I'm going to upload some of these as well when I get a chance. I have like all of them.