downgrading from 2.2.1?

[Guest nvus]

Can I downgrade to 2.2 from 2.2.1? I just bought a nexus and the guy updated to 2.2.1.

[Guest Jo.mogh]

Can I downgrade to 2.2 from 2.2.1? I just bought a nexus and the guy updated to 2.2.1.

Most are reporting a fail with the update.zip method. Need to flash certain ROM with. superboot

[Guest crawler9]

I never upgraded, and I don't want to risk upgrading to test this, but a lot of people are reporting success with the method detailed on this page. If you try it, let me know how it works out. It definitely not as simple as some previous methods, but it should work. If you're able to obtain root, you can download ROM Manager and install a custom recovery from there. You could then install any ROM you chose.

[Edit] I unrooted my Nexus One, just out of curiosity to see if this would work. First I flashed completely stock FRG33 (I think? Whatever the last version of 2.2 was.)including the recovery image by the passimg method. I got the OTA update to FRG83 (2.2.1) and then set to work following the method from the link gave you earlier. I personally have an issue with the clarity of that post; it doesn't really detail what you should do with the Superuser.apk and su files, but if you work through it, it should be okay. Also, I'm not 100% what your goal is. If you truly want to downgrade back to stock 2.2, there will be a few more steps. If all you're after is root access, you don't need to downgrade. My Nexus One was and still is bootloader-locked. It is now running completely stock 2.2.1 with working root access. If you intend to flash a custom rom, you'll still need to install a custom recovery.

[Edit2] More info for anyone who has this same question: If you've received the stock update to 2.2.1, your bootloader will also have been upgraded to a version incompatible with Cyanogen's 6.0 ROM release (without either modifying the ROM update script or downgrading the bootloader.) I didn't realize my bootloader had been upgraded for some time, as I was able to run Cyanogen nightlies without issue. Upon my first attempt to install CM6.0, I thought my file must be corrupt. I knew for a fact that it had to be something else after I tried downloading the file from both a MoDaCo kitchen and Cyanogenmod.com with the same error.

-- Installing: SDCARD:/clockworkmod/download/mirror.kanged.net/cm/stable/nexus/update-cm-6.0.0-N1-signed.zip

I:Set boot command "boot-recovery"

Finding update package...

I:Update location: SDCARD:/clockworkmod/download/mirror.kanged.net/cm/stable/nexus/update-cm-6.0.0-N1-signed.zip

Opening update package...

I:Update file path: /sdcard/clockworkmod/download/mirror.kanged.net/cm/stable/nexus/update-cm-6.0.0-N1-signed.zip

Installing update...

I:Trying update-binary.

installing HTC updater extensions

Welcome to CyanogenMod-6.0.0-N1!script aborted: assert failed: getprop("ro.bootloader") == "0.33.2012" ||

	   getprop("ro.bootloader") == "0.33.0012"


assert failed: getprop("ro.bootloader") == "0.33.2012" ||	   getprop("ro.bootloader") == "0.33.0012"

E:Error in /sdcard/clockworkmod/download/mirror.kanged.net/cm/stable/nexus/update-cm-6.0.0-N1-signed.zip

(Status 7)

Installation aborted.

Failure at line 7:

install_zip SDCARD:/clockworkmod/download/mirror.kanged.net/cm/stable/nexus/update-cm-6.0.0-N1-signed.zip

When I finally read through the error, I looked it up to find that it meant my bootloader did not match the bootloader version for which the update script was looking. After some time, I stumbled across this page. I followed all the instructions there and reverted my boot image from that page and my HBOOT was successfully reverted from 0.35.0017 to 0.33.0012. (The link for the mtd0.img file is dead, but the file can be found attached to post 40 in the topic.) After that, my phone was completely downgraded from my rooted FRG83 to stock EPF30. From there, I used Universal Androot to root my phone and then I installed ROM Manager from the market. I used ROM Manager to flash clockworkmod recovery (my preferred recovery image) and flashed CM6.0 without errors. Since EPF30 is a Eclair build of Android, it'd be important to also obtain a Froyo radio image to flash.

Note: My bootloader is locked. There are easier ways to go about this if your bootloader is unlocked, but I prefer to keep my warranty.

Edited October 5, 2010 by crawler9