So you took the OTA update and lost root. Well you lucked out, but don't do that again!
Warning: There's a lot of steps here, so pay attention. Read the linked posts. I am not responsible if you destroy your phone. At this point there's not much that can be done with root or fastboot or my bootable cwm other than flashing donjuros debloated rom.
This is kind of a process, and you are going to have to download a bunch of stuff.
First step is to read this post.
http://androidforums.com/volt-all-things-root/861292-how-restore-phone-dl-mode.html
Download the file linked from asmugone.
Download the megalock.dll
Follow the steps outlines in the linked post.
Good so now that's done, you get to do more work.
Run towelroot on your freshly downgraded phone. Im not going to bother linking to it, its easily found.
Read donjuros first post here.
http://androidforums.com/volt-all-things-root/872005-rom-zv4-updated-stock-rom.html
Download his modified z4 update.
Read this and then download my CWM build refrenced in this post
http://androidforums.com/volt-all-t...wm-based-recovery-v6-0-3-7-a.html#post6668157
Good? great. Now Read this post.
http://androidforums.com/volt-all-t...r-no-flashing-needed-working.html#post6660832
Still following along? Read below for the people who didn't bother to read the post. Get your phone connected and start adb on your computer.
adb shell
su
dd if=/dev/block/platform/msm_sdcc.1/by-name/laf of=/sdcard/laf.img
Run the following code to zero out laf:
dd if=/dev/zero of=/dev/block/platform/msm_sdcc.1/by-name/laf
adb reboot
power off
hold volume up
plug in usb
You delete the laf partition, which forces fastboot mode and takes the place of download mode.
IF you want to return the phones download mode
fastboot flash laf laf.img
Great so now you are rooted and have the fastboot interface unmasked.
Did you copy over the z4 update to the sdcard? you should probably do that.
Remember that cwm build you downloaded? You dont copy it to the phone, it should be on your computer. PRobably just go ahead and copy it to the root of your adb folder.
Make sure the phones booted into fastboot mode now.
Open up good ole adb.
Run fastboot devices to make sure your computer can find the phone. It should produce a result if it can connect.
This part may be optional:
While in fastboot run
fastboot oem unlock
This "unlocks" the bootloader, not really but im not sure if its needed.
Good? Lets carry on.
Last step.
Fastboot boot cwma1.img (you can rename the img if you wish. I named it cwma1 because it was the first alpha build.)
Now just flash donjuros zip and then you will be updated to z4 and be able to go back in and use towelroot to root it.
This is not really a hand holding exact step by step guide, but there has been a ton of topics lately all asking the same thing.
Warning: There's a lot of steps here, so pay attention. Read the linked posts. I am not responsible if you destroy your phone. At this point there's not much that can be done with root or fastboot or my bootable cwm other than flashing donjuros debloated rom.
This is kind of a process, and you are going to have to download a bunch of stuff.
First step is to read this post.
http://androidforums.com/volt-all-things-root/861292-how-restore-phone-dl-mode.html
Download the file linked from asmugone.
Download the megalock.dll
Follow the steps outlines in the linked post.
Good so now that's done, you get to do more work.
Run towelroot on your freshly downgraded phone. Im not going to bother linking to it, its easily found.
Read donjuros first post here.
http://androidforums.com/volt-all-things-root/872005-rom-zv4-updated-stock-rom.html
Download his modified z4 update.
Read this and then download my CWM build refrenced in this post
http://androidforums.com/volt-all-t...wm-based-recovery-v6-0-3-7-a.html#post6668157
Good? great. Now Read this post.
http://androidforums.com/volt-all-t...r-no-flashing-needed-working.html#post6660832
Still following along? Read below for the people who didn't bother to read the post. Get your phone connected and start adb on your computer.
adb shell
su
dd if=/dev/block/platform/msm_sdcc.1/by-name/laf of=/sdcard/laf.img
Run the following code to zero out laf:
dd if=/dev/zero of=/dev/block/platform/msm_sdcc.1/by-name/laf
adb reboot
power off
hold volume up
plug in usb
You delete the laf partition, which forces fastboot mode and takes the place of download mode.
IF you want to return the phones download mode
fastboot flash laf laf.img
Great so now you are rooted and have the fastboot interface unmasked.
Did you copy over the z4 update to the sdcard? you should probably do that.
Remember that cwm build you downloaded? You dont copy it to the phone, it should be on your computer. PRobably just go ahead and copy it to the root of your adb folder.
Make sure the phones booted into fastboot mode now.
Open up good ole adb.
Run fastboot devices to make sure your computer can find the phone. It should produce a result if it can connect.
This part may be optional:
While in fastboot run
fastboot oem unlock
This "unlocks" the bootloader, not really but im not sure if its needed.
Good? Lets carry on.
Last step.
Fastboot boot cwma1.img (you can rename the img if you wish. I named it cwma1 because it was the first alpha build.)
Now just flash donjuros zip and then you will be updated to z4 and be able to go back in and use towelroot to root it.
This is not really a hand holding exact step by step guide, but there has been a ton of topics lately all asking the same thing.