[Google Pixel Questions & Answers] maxwell0312:
Hello everyone,

I have an OG Pixel 5'', the stock Android was 7.1.2 and I updated it to Android 8.1 Oreo. Bootloader is unlocked, and I am able to install a TWRP 3.2.1-0 no problems. Phone at the time worked well. Now I have tried to flash an ElementalX Kernel on my device. This worked and I managed to boot. However, a message "There is an internal problem with your device, please contact the manufacturer". There is a thread to fix this and I should have done my research better.

Anyway, I went into TWRP and did a complete wipe of the phone, thinking that I could have just boot into TWRP again and copy the stock flashable zips to reflash the ROM.

It turns out that:

a) TWRP doesnt work. I.e when I got into fastboot mode (Power + Volume Down) and selected Recovery, the phone flashed to screen with Google image and then flashed back into the one with the green Android.

b) I managed to boot twrp via fastboot from my computer. So I booted into fastboot mode, and then on my computer, did: fastboot boot <twrp3.2.1.zip>. This worked and I managed to get into TWRP again. However, I cannot transfer file to flash. I.e when the phone showed up on my computer in TWRP, I cannot drag and drop anything into mounted folder.

I have tried the following to get stock ROM from this website: https://developers.google.com/android/images

a) I decided to look at ADB Sideload. So from the above website, I downloaded the zip files under Full OTA Images and then in TWRP, I went into Advance and chose ADB SIdeload. On my computer, I did "adb sideload name_of_zip_file_downloaded". The process started but ended very quickly, the finished time was 0.00 second, which means that nothing happened. Clearly, TWRP console showed that it is unable to mount /data and other folders. I guess the reason is that I am running a "live" TWRP? I checked by going back to TWRP mainscreen and tried to mount. However, all hard drives show 0MB (OTA USB and the main drive).

b) I used factory images approach by downloading zip from the same website, but this time under Factory Images. For this one, I unzip the files to a separate folder. Then I did flash-all.sh script but it said that my fastboot is too old.

So... to fix fastboot, I tried: (I am on Ubuntu 16.04.02)

a) Remove whole android fastboot with sudo apt-get remove, then reinstalled => Did not work. Still fastboot is too old

b) Download entire Android SDK from here: https://developer.android.com/studio/install.html. Fastboot still didnt work

c) From the Android Studio website, I tried to download just the command line tools. However, I could not find the folder with fastboot in it. A Google search shows that the fastboot and adb should be in platform-tools folder. Couldnt find any

Once again, I apologize for a very very long thread (It's 5am and I am trying to figure this thing out). Please, let me know if you guys can offer any help. Any help is greatly appreciated. FYI, I am coming from a Moto Z Play, and if things happen I would just boot into TWRP and copy the zip over. Clearly, this is not the case. This is my 1st Pixel as well.

Please let me know and thank you very very much.