You have updated your One X to a newer version via OTA, then you want to restore the software/ return stock but the latest RUU is not available. (boot to fastboot mode and type the following command "fastboot getvar version-main", This is the true version of your phone!)
You have some basic skills to flash things using "fastboot"
Those who want to back to stock and wait for the JB OTA.
Those with ICS hboot should works without any problem, someone had test it on JB hboot and works(updated in step 6, 7). but we need more testers.
The concept behind.
1. Fool the RUU to make it believe that it is flashing the latest ROM, but actually, we are flashing an older version.
2. after that, boot up the phone with older version of software, then OTA and update the phone to latest software.
How to do that?
0. backup all your stuff including those in SD, all your stuff in your phone will be lost. Then wipe all data (including SD) using your custom recovery. (important! Otherwise, you may not be able to receive OTA).
1. You have to download a "custom RUU" that can be found here.
Feel free to give a thanks to billd2439, he provide this working link to download the custom RUU.
Just go to #115 http://forum.xda-developers.com/show...1#post35139501 and give him a thanks
2. Download the ROM file, it should be in zip format. (You can also extract the rom file by running a RUU, just run the RUU, don't click anything and search the computer for "rom.zip") (In my case, I have an older version 1.29.708.15 rom extracted from RUU)
you may want to find RUU here http://www.htcruu.com
3. unzip the customRUU.zip to a folder, e.g. "customRUU"
4. unzip and extract "android-info.txt", "boot_signed.img" and "system.img" to a folder
5. open android-info.txt with "notepad" (notepad++ is highly recommended)
6. type the following command to get the information from your phone.
fastboot getvar all
you should pay attention to the following information
7. edit the value of "modelid", "cidnum", "mainver" and "hbootpreupdate" to match the information you get from step 6.
by doing this your will try to fool the RUU to belive that you are going to flash a newer version e.g (I have OTA my phone to 2.17.708.7, but now I want to fool the RUU with this old rom with a version number of 1.29.708.15, so I change the value to 2.17.708.7 )
Thanks ahmedaljaf for telling me to modify hbootpreupdate to makes JB downgrade works
8. save the file.
9. zip "android-info.txt", "boot_signed.img" and "system.img" and rename the zip to "rom.zip". (remember only zip the files, not the whole folder!)
10. place the "rom.zip" you just created to the "customRUU" folder
11. make sure your phone is still "unlock", remember to turn on USB Debugging, unplug the USB cable and reboot your phone, then goto fastboot mode and connect the USB cable.
(important, do the above to avoid error messages in RUU)
12. run the file "ARUWizard.exe" inside the folder "customRUU" (see the Attached Readme_Eng.pdf if the customRUU cannot display in correct language)
You can change the customRUU to English version by just delete or rename the language file "ARUWizard_Eng.lng" (Thanks ahmedaljaf for telling me this )
13. follow the on screen instruction,
14. your phone should reboot and boot up with and old version of software.
15. restart the phone and go to fastboot mode.
16. extract the "recovery_signed.img" from your old "rom.zip" (not the rom.zip you create! ) and place it to some where.
17. flash the recovery by typing the following command "fastboot flash recovery recover_signed.img"
18. relock the phone
19. boot up the phone and try OTA
18. if the OTA download finish but fail to reboot to recovery update automatically, just manually boot to recovery and the update will be ok.
If you can return stock with this method, please reply and list the version here. And you can give me a "thanks"