[Transformer TF300T Q&A, Help & Troubleshooting] alexhosu:
This is how i fix my TF300TG stuck on recovery. I hope the steps descried below will help.

Long story, short:

For some reasons, seems like the WIPE command from TWRP and CWM recovery screw the partitions.

No partitions or microSD card can be mounted.

The tablet is now booting only in recovery mode or in fastboot mode (the screen with three icons - RTK, Android and WIPE) instead of Android.

IMPORTANT:

If your tablet reboot in fastboot mode DONT WIPE IT AGAIN! Just skip step 4.

First of all, MAKE SURE YOR BATTERY IS CHARGED!

Recharge your tablet for at least two hours.During the flashing process the tablet doesn`t charge.

Use the original Asus USB cable that came with the tablet or a high quality replacement cable. Cheap cables can and will cause problems.

Use a laptop or desktop with known good USB ports. If you have problems, try a diferent computer, some USB chips can cause troubles.

Disable the antivirus or screensaver, sleep etc...

1.Download these files:

from ASUS website: http://www.asus.com/Tablets_Mobile/ASUS_Transformer_Pad_TF300TG/#support

Drivers&Tools, on the OS tab select Android

click on Utilities and download latest version of ASUS PC Sync (you will need this for drivers)

click on Firmware and download the lastest available (you will need this for BLOB file)

Minimal ADB and Fastboot: http://d-h.st/gbx

install ASUS PC Sync and Minimal ADB and Fastboot (on fastboot installer check the box that make a shortcut to desktop)

unzip the firmware file downloaded from ASUS site

you will get a second zip file, unzip this one too

the folder unzipped from the second one contain a file called blob

copy or move the folder to the root of your drive C: or D: or whatever drive letter you have

2.Installing drivers:

connect your tablet to PC

you will get a message about Windows couldnt find driver bla...bla, ignore it and keep your tablet plugged

IMPORTANT: even if you previously installed ASUS PC Sync or other drivers and Windows recognize your tablet, you still need to change the driver.

right-click on My Computer-Properties and click Device Manager

find the Asus Android device - should be with an exclamation mark on it (the driver is not installed sign)

right-click on it and choose:

Update Driver Software..., Browse my computer for driver software, Let me pick from a list of device drivers on my computer, Have disk, Browse

go to C:\Program Files or Program Files (x86), ASUS, ASUS Android USB Drivers, Android and select android_winusb.inf

Asus Android Composite ADB interface will appear in the list of device drivers - don`t hit next yet!

uncheck Show Compatible Hardware and select Asus Android Bootloader Interface from the list, now hit next

3.ADB mode:

open Minimal ADB and Fastboot from desktop - from this point, keep it open

type: adb devices - and you should see some numbers under the List of device attached - thats your tablet

if you can`t see the tablet, try this command: adb start-server

4.Booting to "fastboot":

there are two ways to do this:

a) from adb window type: adb reboot bootloader

or

b) reset and hold vol-down (didn`t work for me, but maybe will work for someone else)

the three icons will appear on screen - NOW YOU ARE IN FASTBOOT MODE

if none of the above work try this:

in adb window type: adb reboot

wait until the tablet enter in recovery menu and type in adb window:

adb shell dd if=/dev/zero of=/dev/block/mmcblk0p3

adb reboot bootloader

5. Flasing the blob

the credits for this part goes to buster99. He is the one who figured out the right commands for formatting partitions and flashing back the OS

here is his post: http://xdaforums.com/showpost.php?p=44244313&postcount=12

here we go, one at the time in adb window:

fastboot erase system

fastboot erase recovery

fastboot erase userdata

fastboot erase boot

fastboot erase misc

fastboot erase cache

fastboot -i 0x0B05 flash system x:\your blob folder\blob (here you enter the path to your blob file, must end with blob, to point at the file)

fastboot -i 0x0B05 reboot

THE FLASH SYSTEM COMMAND WILL TAKE SOME TIME

be pacient and wait until the progress bar is 100% full on the tablet and you get the command prompt back in the adb window.

After reboot, the Android is back on.

Cheers and good luck!!