No valid OS found

[MichaB189]

Im building clean AOSP with android-prepare-vendor

repo init -u https://android.googlesource.com/platform/manifest -b android-9.0.0_r40
repo sync

I remove AOSP/vendor/google_devices/*

PQ3A.190605.003 matches android-9.0.0_r40

sudo ./execute-all.sh -d blueline -b PQ3A.190605.003 -o out

I copy the files generated:
from:
/android-prepare-vendor-master/out/blueline/pq3a.190605.003/vendor/google_devices/*
to: AOSP/vendor/google_devices

I then run make clean
make clobber
make -j12

cd AOSP/out/target/product/blueline
fastboot flashall -w

adb reboot bootloader
fastboot flashing lock

No Valid OS found
g.co/ABH

Am I missing something, either regarding copying the right files from android-prepare-vendor or something other?

[scott-8]

Does it boot with the bootloader unlocked (i.e. don't run fastboot flashing lock after flashing the image and boot it)? You might need to flash the phone with the key you used to sign the image with fastboot flash avb_custom_key key_name.bin before locking it.

[anestisb]

@MichaB189 do you still face the issue?

[MichaB189]

Yes it does boot with the bootloader unlocked.

I tried again now. WIth the August 2019 version - pq3a.190801.002. As I've heard there are some issues with Android 10

[MichaB189]

Does it boot with the bootloader unlocked (i.e. don't run fastboot flashing lock after flashing the image and boot it)? You might need to flash the phone with the key you used to sign the image with fastboot flash avb_custom_key key_name.bin before locking it.

Thanks!
I did not do that. Could you supply me with additional information regarding signing?
I had factory images from Google before flashing my vanilla AOSP build with android-prepare-vendor. Is there some in depth tutorial explaining the process of signing the keys, what keys I should sign and so forth? Thanks again!