[General Questions and Answers] tabletmonkey:
I work at a electronics recycling business. A tablet came in, ASUS ME176CX according to the serial, that had a app called SureLock on it. Basically, the tablet is locked to only showing one app and I don't have the admin password to unlock it. I thought I'd just go in to recovery mode and wipe it back to factory defaults. I did find some sort of wipe/reset option by holding down buttons during boot. Though, as I recall, it didn't say exactly "factory reset" which I thought was odd. I used it but doing that didn't remove the SureLock app. Then I couldn't figure out how to get back to the menu.

I could get in to Fastboot (hold down Volume up and Power and release power after seeing the logo) and select Recovery but after that I only got a picture of a droid on it's butt with a red triangle and exclamation mark. So, I Googled a bit and found a guide that told me how to put fastboot on my PC and how to wipe 3 things and write 3 things, I think, to the tablet connected by USB while in Fastboot mode with the goal of bringing back a recovery menu. The wiping parts worked but the writing parts failed. I just got an error message. After that the tablet stopped booting correctly. It would get stuck at the ASUS logo and didn't show the animated Intel logo below.

Then I figured out how to get TWRP 2.8.7.0 to run on the tablet. I tried some steps in a Youtube video but couldn't copy the ESP.img file because the /dev/block/by-name doesn't exist on my tablet. Maybe I have an older version of Android on it. I suspect the instructions were made for Android 5 and I have 4.

Next I just went in TWRP, Install, and selected the last firmware released by ASUS for the tablet, as a zip file, and tried installing it but I get a error message telling me E: Error executing updated binary in zip '/external_sd/UL-K013-WW-12.10.1.17_KK-user.zip'. I get the same error if I try the earliest firmware from the ASUS download page. I have read that I might be getting this error because I am using an old version of TWRP but the TWRP website doesn't have a download specifically for my device so I'm not sure where to try getting an update.

I tried using the ADB Sideload feature of TWRP. I was told there is a mismatch of versions of ADB on my computer and the tablet. So, I tried downgrading the version of ADB on by computer to match and reran the sideload command. It just told me there was an error and the sideload failed.

Then after Googling a bit more I finally figured out how to get to the Android recovery menu. I have to hold down both volume buttons for about 12 seconds while seeing the droid with the red triangle. I then tried a wipe data/factory reset which didn't succeed in fixing my problem of not getting past the ASUS logo during boot.

So, nothing is working and I don't know why. Can I get some help? I want to get the tablet back to a working state. I did figure out how to get TWRP running on the tablet and figured out how to get in the recovery menu.

While typing this I tried going in to the tablets recovery menu, apply update from ADB, and then used ADB on my PC to upload UL-K013-WW-12.10.1.17_KK-user.zip which was downloaded from ASUS. While the tablet was installing the update there were a couple errors.

Installing Update...

E:Error in /tmp/update.zip

(Status 0)

E: fota_return_code 409

Installation aborted.

Might I be able to get a used ME176C from someplace and make a full backup of it and put it on this messed up tablet, a ME176CX?