[Transformer TF300T Q&A, Help & Troubleshooting] lj50036:
This is a general users guide to unbrick your Transformer tablet.

This guide will help you if your Asus tablet will only boot into recovery

and the command

adb reboot-bootloader

does not work to get you booted back to bootloader screen ..

If the above command works then skip to the first fastboot command ..

WHAT YOU NEED

An Asus tablet that will only boot into recovery …

Woking adb and fastboot on your PC

Windows drivers (if using Windows)

A fully charged tablet

Asus data cable

Stock firmware blob (from Asus's web site, make sure you get the right one)

_that's bootit.ko (unzipped and placed with fastboot.exe)

Downloads

Asus Stock firmware---MAKE SURE YOU GET THE CORRECT SKU FOR YOUR TRANSFORMER TABLET

click me

_that's bootit.ko----click me

INSTRUCTIONS

Extract your stock firmware in your downloads folder twice...You will see a blob file rename it boot.blob and move it to the same folder as your fastboot.exe or if in linux to your home folder

Unzip the bootit.ko and place it wth the above blob file.

Let start with this command to make sure that your PC can see your table as an ADB device in recovery

adb devices

OUTPUT

lj50036@area51 ~ $ adb devices
List of devices attached
015c7d7a445c260c	recovery

Then lets push the bootit.ko to the root of the device like this

adb push bootit.ko /

OUTPUT

lj50036@area51 ~ $ adb push bootit.ko /
673 KB/s (27690 bytes in 0.040s)

Then lets insmod this .ko file

adb shell insmod /bootit.ko

This should reboot the tablet into the bootloader menu, lets verifiy.

Once in the bootloader screen lets make sure your PC can see the device in fastboot.

fastboot devices

OUTPUT

lj50036@area51 ~ $ fastboot devices
015c7d7a445c260c	fastboot

So now its time to erase the misc & cache partitions, as that is most likely the partitions that is making it boot to recovery...

fastboot erase misc

OUTPUT

lj50036@area51 ~ $ fastboot erase misc
erasing 'misc'...
OKAY [ 1.021s]
finished. total time: 1.021s

fastboot erase cache

OUTPUT

lj50036@area51 ~ $ fastboot erase cache
******** Did you mean to fastboot format this partition?
erasing 'cache'...
OKAY [ 2.096s]
finished. total time: 2.096s

Once these two command run with OKAY as the OUTPUT .

It is time to make sure we can reboot into the bootloader with the hardware buttons

So from where you are at in the bootloader screen use the VOL DOWN & POWER buttons to boot the tab back into the bootloader screen ..

Run these command in fastboot in this order

The next command is to just verify your computer can see your device

fastboot devices

OUTPUT

lj50036@area51:~ > fastboot devices
015d2bbce2501405 fastboot

fastboot erase system

OUTPUT

lj50036@area51:~ > fastboot erase system
******** Did you mean to fastboot format this partition?
erasing 'system'...
OKAY [ 2.954s]
finished. total time: 2.954s

fastboot erase recovery

OUTPUT

lj50036@area51:~ > fastboot erase recovery
erasing 'recovery'...
OKAY [ 1.945s]
finished. total time: 1.945s

fastboot -w

OUTPUT

lj50036@area51:~ > fastboot -w
erasing 'userdata'...
OKAY [ 23.188s]
formatting 'userdata' partition...
Creating filesystem with parameters:
Size: 29618601984
Block size: 4096
Blocks per group: 32768
Inodes per group: 8192
Inode size: 256
Journal blocks: 32768
Label:
Blocks: 7231104
Block groups: 221
Reserved block group size: 1024
Created filesystem with 11/1810432 inodes and 157662/7231104 blocks
sending 'userdata' (139133 KB)...
writing 'userdata'...
OKAY [ 26.358s]
erasing 'cache'...

At this point it will either hangs on erasing 'cache'

Or it will give you an error, either way you will need to

reboot the tablet back into fastboot with the hardware buttons

Once that is done continue on the path

fastboot erase boot

OUTPUT

lj50036@area51:~ > fastboot erase boot
erasing 'boot'...
OKAY [ 1.209s]
finished. total time: 1.209s

fastboot erase misc

OUTPUT

lj50036@area51:~ > fastboot erase misc
erasing 'misc'...
OKAY [ 0.978s]
finished. total time: 0.978s

fastboot erase cache

OUTPUT

lj50036@area51:~ > fastboot erase cache
******** Did you mean to fastboot format this partition?
erasing 'cache'...
OKAY [ 2.843s]
finished. total time: 2.843s

fastboot -i 0x0B05 flash system boot.blob

During the sending/writing process of this step you will get the blue bar on your screen.....

OUTPUT

lj50036@area51:~ > fastboot -i 0x0B05 flash system boot.blob
erasing 'system'...
OKAY [ 2.339s]
sending 'system' (800927 KB)...
OKAY [133.094s]
writing 'system'...
[OKAY [178.036s]
finished. total time: 313.469s

fastboot -i 0x0B05 reboot

OUTPUT

lj50036@area51:~ > fastboot -i 0x0B05 reboot
rebooting...
finished. total time: 0.020s

Let it boot into stock ROM ....