Just thought I'd provide a warning and a fix to a half day ordeal recovering from a soft-brick after wanting to make the switch from TW to WWE.
What made this all go wrong?
I have a Padfone 2 which had the latest TW_A68-10.4.17.15
I have a accidentally turned off adb USB debugging mode
I unlocked my bootloader using the ASUS official unlocker.
I had then install 220.127.116.11 twrp which didn’t work
Install 18.104.22.168 twrp which did.
Forgot to do a backup which I usually did, but guess I thought that I have done this so many times, nothing would go wrong.
DON’T GET COCKY BACKUP FIRST.
Opted for the easy way out and write to system VIA twrp using zip, which was reported to work.
This installed and didn’t report any error.
After reboot, app.phone and another OS programs crashed constantly and rebooted.
I removed my sim and this stopped the crashed apps, but not the reboots.
I realised I was in a whole world of trouble and it was only at this moment did I realise that I didn’t have USB Debugging turned on. Frantically tried to enable it in between reboots, but failed and was now presented with only a ASUS spinning circle of death, or even better later, only the which ASUS logo before it reached it.
All I had available was fastboot and twrp.
You’d think this was an easy fix, but I didn’t have a usable/original rom on the /data/media a.k.a /sdcard partition.
Note: have a handful of roms including your original rom saved on the phone before trying anything, as this phone has no access to external storage when all goes pear shaped.
I wiped caches, didn’t work.
I then wiped data, which then deleted the only rom I had access to. So I couldn’t even now retry installing from zip.
ADB didn’t work from any recovery including CWM 22.214.171.124
I was at a loss and didn’t know what to do.
Installed twrp 126.96.36.199 was persistent with ADB sideload, even though I didn’t have USB Debugging enabled.
Note: ADB sideload will still work even if you don’t have USB Debugging enabled. It’ll either take a min or two to register on your computer, but if not reboot and reboot again to get it to register.
Sideloaded the wrong firmware file again.
Note: If you are trying to sideload the original firmware, extract the zip “TW_PadFone2_user_10_4_17_15_UpdateLauncher.zip” and sideload the zip hiding within “ASUS” -> “Update” -> “TW_A68-10.4.17.15-0-ota-user.zip”
After another long time trying to get the ADB device to register, finally got a second chance and got back to the original firmware.
Did this deter me from the switch from TW to WWE. HELL NO!!
Enable ADB USB Debugging
Make sure you push the rom WWE to your /sdcard partition
How to do it right.
Load the original recovery attached recovery.stock.img
Reboot into recovery and select "apply update from external storage" and choose the zip file to flash.
This will fail! It's what it's meant to do
At this point the recovery changes the partition table and then restarts.
On reboot we will have a nice "Installation aborted", this because, being changed the partition table, the recovery can not find the file to flash as it the partition containing the data has been reformed losing its contents. So you will need to copy the file again via adb.
Select "wipe data / factory reset"
You need to do a wipe, because it formats the partition where we will send the file. Having just changed, the partition has not a file system and so it must be formatted to save something on it.
Upon rebooting to ADB stopped working under the stock recovery. It registered with my computer but the command to repush the WWE rom to /data/media kept failing.
Rebooted into fastboot and install twrp 188.8.131.52. At this stage as I knew that the partition table had been updated, I sideloaded the WWE rom, which works more reliably when it's originally enabled
Did a Wiped cache for safe measure
Reboot and welcome to another 2GBs of space and WWE firmware.
NOTE: Always flash the inner zip “TW_A68-10.4.17.15-0-ota-user.zip” not the outer zip “TW_PadFone2_user_10_4_17_15_UpdateLauncher.zip”