[One (M8) Q&A, Help & Troubleshooting] arvo.bowen:
Solution Steps

OK, so this turned out to be a long bumpy road. Everytime I go to upgrade my phone I have the same thought... First it's ahh no, phone is going to be DOA for about 2-3 days, and second I think "Why is there not a single page (that stays up to date) with an easy to follow tutorial on how to do this whole process??". Don't get me wrong, we would be nowhere without XDA but usually (due to lack of staying up to date) on the site I always feel like it's way to cluttered and complicated to find the "right" path.

Luckily I found a few people along the way to help me out. The Viper team over at http://venomroms.com/tickets were really great in keeping me pointed back on the right track. With their help and a LOT of reading on the web once again I managed to come out of the dark with an upgraded phone. Here are the steps that I came up with.

Note: Theses instructions are all based on using Windows, if someone wants to add to this thread with Mac instructions be my guest to copy paste all this and change content to suit Mac purposes.

Note: My phone is both *UNLOCKED* and S-OFF. If your phone does not show this in the bootloader screen at the top then the following might not work.

Note: When I say type 'this text'. Don't type the quotes unless they are bolded. It's VERY rare that they are needed! This is what it 'looks like' when the quotes are bolded as well.

Setup your phone for use with ADB/FastBoot

- Go into Settings, About, Software Information, More.

- Tap Build Number SEVEN times to enable developer mode.

- Go back to Settings, Developer options.

- Make sure Developer options is turned on at the top.

- Scroll down to Debugging area and make sure USB debugging is enabled (checked).

- Go back to Settings, Power and IF (depending on what OS you are in) you have a setting for fastboot, just uncheck it so you can get into the bootloader a little easier.

- At this point you should have your phone with USB debugging turned on so you should be set!

Download the latest Android Platform Tools:

- You can find the SDK here if you want to go through the long process (takes forever!) of getting the new tools OR for speedy results you can download a package that is a 100% replica of just the "platform-tools" directory that you need out of the SDK located here.

- Extract these tools into any directory (for example c:\tools\) and from this point on they will be referred to as "the tools directory".

Get the command window ready to do work:

- While in the tools directory, hold shift and right click in some EMPTY area within that folder. You should now see a sub menu option that says "Open command window here". Click it and get that command window open.

- Now if you have not already, connect your phone.

- In the command window type 'adb kill-server'. This is to ensure your device list will be clean and you only see your phone connected.

- Type 'adb devices'. To get a connection to your phone. You should see something like this...

C:\tools>adb devices

List of devices attached

* daemon not running. starting it now on port 5037 *

* daemon started successfully *

FA45WSF03873 device

- If you see that last line showing you your device and says "device" next to it, everything is great and you can continue. If not, if it says 'disconnected' or something similar then you need to work on getting that fixed before you can go any further.

Download and flash the L hboot (version: 3.19.0.0000):

- Go here and download the vzwm8Lhboot.zip file.

- Rename the zip to '0P6BIMG.zip'.

- Put zip on root of sd card (aka external memory).

- Reboot phone to bootloader (power off, then hold VOL DOWN and POWER)

- In bootloader, "Do you want to start the update?" Press VOL UP (for yes)

- Press POWER button for reboot.

- Wait for phone to boot back up to OS and use PC to browse SD card.

- Remove (delete) the 0P6BIMG.zip file from the sd card.

Update TWRP to latest stable (version: 2.8.7.0):

- Go here and grab TWRP and save it to the tools directory. Side note, I noticed the URL says GSM and with Verizon you should be using CDMA. But the links I followed on their page said "All Variants" so I guess there URL is just named weird because it works perfectly fine for me.

- Under Download Links, click on the Primary (Recommended) link and grab a copy of TWRP (twrp-2.8.7.0-m8.img).

- Save that file to the tools directory and rename it to 'twrp.img'.

- Now we need to get the phone to boot up to the bootloader screen. There are a few different ways to do this but the easiest way that people usually don't get confused is the following... Power off your phone. Once off hold down the VOL DOWN key, and then ALSO hold down the POWER button UNTIL you see a white screen with a bunch of green text at the top and three little androids skateboarding at the bottom.

- Navigation is easy while in the bootloader screen. VOL UP moves you up in the list and VOL DOWN moves you down. Pressing (not holding) POWER will select the option you are on.

- Make sure the selection is on 'FASTBOOT' and press POWER to select it.

- Over on the PC in the command window (where you should still be in the tools directory) type 'fastboot flash recovery twrp.img'.

- You should get a success message.

Update the phones firmware:

- Go here and grab the 'VZWm8LfirmwareTWRP.zip' file. This will upgrade some very important things.

- Save this file to the tools directory.

- In the command window type 'fastboot oem rebootRUU'. The phone should change to the silver HTC logo screen.

- In the command window type 'fastboot flash zip VZWm8LfirmwareTWRP.zip'. This will start a long process that DOES NOT NEED TO BE INTERRUPTED!!! Go get a pizza or something just leave the phone alone!

- After about a minute or two when it finishes in the command window type 'fastboot reboot-bootloader'. This will get you back to the bootloader screen so you can confirm the new versions.

Android 5.0.1

CID-VZW__001

HBOOT-3.19.0.0000

RADIO-1.12.20.1211

OpenDSP-v47.2.2-00564-M8974_FO.1024

OS-4.17.605.5

eMMC-boot 2048MB

Feb 3 2015,21:50:28.0

- Get back to the menu on the phone and select the 'REBOOT' option then press POWER. The phone will boot back the the Android OS.

Install the new Viper ROM (version: 4.3.0):

- Now grab a copy of the Viper ROM from here. Click on "Previous roms" and choose "ViperOneM8 4.3.0".

- Save this to your SD card as the default name 'ViperOneM8_4.3.0.zip'.

- Boot into recovery by powering down the phone, holding VOL DOWN and POWER until you get to the bootloader screen and then choosing 'RECOVERY'. This should get you into TWRP.

- While in TWRP choose install and choose the Viper ROM you just added to your SD card. The location is at '/external_sd/'.

- This should take you through the Viper setup. Just follow the steps on screen at this point!

References:

- Venom ROMs - A great team of guys with great ROMs.

- Venom Helpdesk Ticket System - A place to submit tickets to get help when trying to install Venom ROMs.

- XDA Thread By dottat - A place I found my L hboot update and learned a few things.

- XDA Thread By Tigerstown - A place I found my new firmware to upgrade to Android 5.0.1, hboot, radio, etc.

- VenomOneM8 ROM - This is where I was able to download my VenomOneM8 4.6.0 ROM that I use for my HTC One (M8).