ATT v20. Cant boot into bootloader..

[t0xicdr3am]

I have a ATT v20 and ive been trying to root and put TWRP on it but cant seem to get into the bootloader or recovery or download mode.
Tried typing adb reboot bootloader and it just restarts the phone pretty much. Any help would greatly be appreciated.

 

[ver2go]

No bootloader stock. You have to go through this procedure

https://forum.xda-developers.com/v20/how-to/root-h910-v10m-t3664500

 

[t0xicdr3am]

I tried too but cant seem to get it to boot into download mode

Sent from my LG-H910 using Tapatalk

 

[runningnak3d]

@t0xicdr3am What version of the firmware is on your phone? What happens when you have the phone powered off, hold vol up and plug in the USB cable?

-- Brian

 

[t0xicdr3am]

The only things I've been able to get it to do is display two barcode thingy screen. I got it into recovery by typing adb reboot recovery and it displays an android guy with an exclamation mark but no options. Tried to upload a screenshot but tapatalk won't let me lol.

Sent from my LG-H910 using Tapatalk

 

[t0xicdr3am]

Says software version h91010m..

Sent from my LG-H910 using Tapatalk

 

[ver2go]

Just got mine the other day one the same version.

Phone powered off.
UBB Cable plugged into PC
Vol UP
Insert other end of cable into Phone.

 

[t0xicdr3am]

Just got mine the other day one the same version.

Phone powered off.
UBB Cable plugged into PC
Vol UP
Insert other end of cable into Phone.

Ill try that again but pretty sure it didn't work for me. My son's on my PC but he goes to bed soon and then ill try it and report back. Thanks dude.

Sent from my LG-H910 using Tapatalk

 

[t0xicdr3am]

Okay so following that tutorial he posted.. I get up to about STEP2.BAT.. Tons of static screens and Im not sure if I messed up my phone for good or not..
My phone has the H915 firmware or whatever from the KDZ.. I dumped my system so Im not sure if that saves me or not?

 

[t0xicdr3am]

Also have no cellular signal..
I try following that tutorial to the T but idk what im messing up

 

[t0xicdr3am]

Could really use some help guys..

Pretty much stuck on the H915 KDZ I flashed with no cellular.. Following the steps on the H910 tutorial doesnt work.. I get to past Step 1 and either Step 2 messes up or it boots into step 3 and tells me fastboot isnt a valid command or something....

 

[t0xicdr3am]

Okay so I got TWRP on it.. but when I try to do anything, its like it doesnt mount system.. I try to flash the system.zip and system.img and i get unable to mount system (unknown error 150)..

Then I go to reboot recovery and it says no OS installed.. So Im assuming when I flashed the system.img it erased the OS?

 

[ver2go]

Now you need to do this part to complete

Now that you are in TWRP you need to do a couple of things:

 

[t0xicdr3am]

Now you need to do this part to complete

I did.. I flashed the 10m zip and flashed the system.img.. made sure not to get any mount errors..

So it flashed successfully.. rebooted system and it gave me a kernel error im assuming so I held down volume down to restart as it said and now its on the LG screen.. waiting to see if boot time just takes longer or what not and Ill report back..

But shouldnt I have data and cellular? Im on Cricket which is apart of ATT and in his post after flashing the KDZ file.. it says I should but I dont..

At this point I really dont want any root or anything.. I just want to restore my phone to a working state with cellular as I have a young son and use my phone for work and my stupid ass shouldnt of been ****ing with it from the beginning lol.. If I can get back to 10m or stock or whatever and the modem works ill be happy..

I have a full dump from that one step.. Will that help me revert these changes back? How do I go abouts using the DUMP to restore?
Sorry.. never used a dump before.. If it'll even work

 

[t0xicdr3am]

Okay so no luck.. maybe TWRP didnt give me an error but when I went to reinstall the files again because i waited 10 mins.. it gave me the unable to mount system unknown error 150.. any ideas?

 

[runningnak3d]

If you have a Cricket H910 it may be different than an normal H910.

Did you take a dump of your firmware before rooting? It is an optional step, but I hope you did.

-- Brian

 

[t0xicdr3am]

If you have a Cricket H910 it may be different than an normal H910.

Did you take a dump of your firmware before rooting? It is an optional step, but I hope you did.

-- Brian

I did but have no idea how to restore it using the files it pushed onto my computer.. It isnt a cricket H910.. Its an ATT H910.

Side note, good morning Brian.. Been waiting for you lol

 

[t0xicdr3am]

Is there anyway one of you guys can point me into the direction of using the DUMP to restore whatever I can?

 

[t0xicdr3am]

Now you need to do this part to complete

When I go to flash the system.zip and .img it erases system completely and then I get the unable to mount system (unknown error 150)

Im pretty sure this all has to do with the encryption.. When I go to format data, it cant mount storage.. When I finally get it to format; and I flash the system.zip and .img i get the unable to mount system..

I dont even want root anymore.. I just want to know how to use my DUMP to fix my phone if its possible?

 

[runningnak3d]

If it is an AT&T H910 then there is a thread, linked to in the post about rooting that will get you back to stock.

However, I warn you, if you can't make this work, then the chance of you restoring to stock are not good.

I can tell from the posts / PMs that you made, that you didn't read the entire post before trying to root.

You have asked questions that are answered right in the post.

-- Brian