[Samsung Galaxy Nexus] jeff72k:
Procedure I followed to flash to takju (Android 4.0.4) from yakjuux (Android 4.0.2)

Note: This assumes you have the Windows drivers installed and working on your computer and fastboot (platform-tools-v19.zip) installed and working.

(Driver information and the fastboot (platform-tools-v19.zip) download can be found at this other yakju link: http://xdaforums.com/showthread.php?t=1626895)

Galaxy Nexus images found here

: https://developers.google.com/android/nexus/images#takju

takju image: https://dl.google.com/dl/android/aosp/takju-imm76i-factory-e8c33767.tgz

Factory Images "takju" for Galaxy Nexus "maguro" (GSM/HSPA+) (with Google Wallet)

Version 4.0.4 (IMM76I)

MD5 Checksum 26ede55c44b503e4ab02969c22fa16e1

SHA-1 Checksum	e8c33767bfc9fbb360b72b26f4e9a41a2e4c74c4

Backup any application data and sdcard files off of your phone

I use Dropbox to upload my files onto the remote Dropbox share

Some suggestions on what to backup from your phone:

Alarms (any regular alarms you have set on your phone (wakeup at 7am, etc...))

Pictures + Movies

Screen shots

Shopping list + Todo list

Sync to Google (phone book, app data (Wi-Fi settings, etc...))

Settings - Accounts & sync - (click on your Google account) - uncheck Sync Contacts - check Sync Contacts

Sync any other things in the same way, such as Calendar, Gmail, etc...

Settings - Backup & reset - check Back up my data

Settings - Backup & reset - check Automatic restore

Factory Reset phone (make sure you have backed up any phone data you want off of your phone)

Settings - Backup & reset - Factory data reset

Once your phone is done with the factory restet and reboots and at the Welcome screen, then do this:

Start - Not now - Next - Next - Next - Finish - OK

Power off your phone when you are at the main screen

Clockwork backup - backup your original phone image using clockwork backup

Original efrant post here: http://xdaforums.com/showpost.php?p=21266325&postcount=239

Step-by-step

1) Note: this assumes that you have the drivers and fastboot for your device set up properly and that you have backed up any

data (e.g., photos, etc) to somewhere OFF your device;

2) Download recovery-clockwork-5.5.0.2-maguro.img and place the file in the directory on your PC with the fastboot command;

http://download.clockworkmod.com/recoveries/recovery-clockwork-5.5.0.2-maguro.img

3) Reboot your device into bootloader mode (by turning it off, hold volume up and volume down, and press power) and

plug it into your computer;

4) Open a command prompt in the same directory above and do the following:

a) Make sure your computer recognizes your device by typing: fastboot devices

b) If your bootloader is unlocked already, skip to part c below.

Unlock your bootloader if not done already: fastboot oem unlock

You will see a prompt on your device. This will wipe your entire device (including the /sdcard folder). Accept.

Reboot by typing: fastboot reboot-bootloader

Boot into the OS: fastboot reboot

Once at the main screen, power off the phone.

Boot the phone into fastboot mode.

c) Boot CWM: fastboot boot recovery-clockwork-5.5.0.2-maguro.img

d) Now, on your device navigate the menus to back up your existing build

Volume down button until you highlight "backup and restore" and press power button

While highlighting "backup" press the power button

Wait about 5 minutes for your phone to backup it's files to the internal SD Card memory storage.

When the backup has finished, select "reboot system now"

e) Now you have a complete backup of your current build in /sdcard/clockworkmod/backup.

Save this to your computer as well.

After reboot, Windows 7 should show your phone as a USB storage device.

On your PC, click on Internal Storage - clockworkmod - backup

Copy the directory that looks similar to this to your PC drive to backup your phone image:

Example: 2012-04-24.20.37.05

Note: my yakjuux 4.0.2 clockwork backup directory was 360MB in size total

If your phone bootloader is oem unlocked (if you did the above clockwork backup), then skip to "Fastboot mode" below.

If you skip the Clockwork backup, then make sure your phone bootloader is oem unlocked so you can run fastboot

Unlock your bootloader if not done already: fastboot oem unlock

You will see a prompt on your device. This will wipe your entire device (including the /sdcard folder). Accept.

Reboot by typing: fastboot reboot-bootloader

Boot into the OS: fastboot reboot

Once at the main screen, power off the phone.

Boot the phone into fastboot mode.

Fastboot mode and extract takju files

Power off phone with USB cable connected to phone and to your computer

Enter your phones "fastboot" mode by holding "volume up" and "volume down" then press the "power" button

Use 7-zip to examine takju-imm76i-factory-e8c33767.tgz and extract the takju-imm76i directory with your takju files onto your computer.

Open a Command Prompt on your computer and type the following to get to your takju files:

c:

cd \path-to\takju-imm76i

dir

You should now see your takju files including:

bootloader-maguro-primela03.img

flash-all.sh

flash-base.sh

image-takju-imm76i.zip

radio-maguro-i9250xxla02.img

Verify you can see your Galaxy Nexus:

fastboot devices

If you can't see your Galaxy Nexus with "fastboot devices" then:

Make sure your phone is connected to the usb cable and the usb cable is connected to your PC

Make sure you booted your phone into "fastboot" mode, see above.

optional: Erase your phones current old images

(I do not know if this part is necessary, but I was rooted before, so I chose to erase everything as follows to "unroot")

(Note: Only do this when you are ready to do the "Flash your phone" part below right after this part)

fastboot erase boot

fastboot erase system

fastboot erase userdata (Note that this command will wipe all your data, including /sdcard)

fastboot erase recovery

fastboot erase cache

fastboot reboot-bootloader

Flash your phone

(Note: the following commands are taken directly from the flash-all.sh script file that comes with the takju-imm76i-factory-e8c33767.tgz file from Google)

fastboot flash bootloader bootloader-maguro-primela03.img

fastboot reboot-bootloader

sleep 5 (count to 5 then continue)

fastboot flash radio radio-maguro-i9250xxla02.img

fastboot reboot-bootloader

sleep 5 (count to 5 then continue)

fastboot -w update image-takju-imm76i.zip

Note: This is normal:

archive does not contain 'boot.sig'

archive does not contain 'recovery.sig'

archive does not contain 'system.sig'

When the image-takju-imm76i.zip finishes, your phone will reboot a few times to setup the new system. This is normal. This took my phone 1 or 2 minutes to finish.

You are done when you get to the Welcome screen.

Thanks go out to everyone who has contributed to the above information, some of which include:

efrant = Convert to yakju - Official Google OTA update URLs - How to back up your current build

eddie_gordo