I had the same problem (`Your device is corrupted…`) and it occurred directly after the online update to FP3-6.A.040.2.
The “corrupted” error was reported always during normal android boot procedure (tried > 20 times) and when booting into recovery mode.
I executed the mentioned steps:
- `fastboot flash devinfo devinfo-unlocked.gpx` of the post Fairphone 3 unlocking without oem unlocking
- Executing a FP3-6.A.039.7-gms-44ba459b-user-fastbootimage installation via `./flash_fp3.sh`.
At the end of this step the question comes to relocked the bootloader. After the following reboot the phone was erased - so all data lost!
The same is true for my FP3, so updating to the firmware FP3-6.A.040.2 seems to brick the device if it was unlocked at some time in history. Unbricking is possible, but ASAK not to the previous state (=bootloader locked) without loosing all data.
I strongly recommend performing a backup of all important apps before updating!
Update of 3 hours later: The newly performed online update for to FP3-6.A.040.2 after a clean installation of FP3-6.A.039.7-gms-44ba459b-user-fastbootimage bricked the FP3 again - same error message (…corrupt…). Now I directly used FP3-6.A.040.2-gms-d33dc62f-user-fastbootimage and pray the next FP3-Version does not brick my FP3 again.