I have OnePlus One with CyanogenMod 12 from factory and I decided to update to CM 13 (nightly build).
To achieve this I did the following from OSX:
- Unlock the bootloader (fastboot oem unlock)
- Boot TWRP (fastboot boot twrp-188.8.131.52-bacon.img)
- From TWRP I installed CM 13 (cm-13.0-20160105-NIGHTLY-bacon.zip) and GAPPS (open_gapps-arm-6.0-pico-20160105.zip)
- I also installed the latest Cyanogen Recovery (cm-13.0-20160105-NIGHTLY-bacon-recovery.img)
- For some reason, I felt like leaving things as they were, and I relocked the bootloader (fastboot oem lock)
Now, I cannot unlock the bootloader anymore in order to do things like install/boot a custom recovery tool (like TWRP)
Running 'fastboot oem unlock' just reboots the device in recovery mode, but the bootloader remains locked:
$fastboot oem device-info ... (bootloader) Device tampered: true (bootloader) Device unlocked: false (bootloader) Charger screen enabled: false (bootloader) Display panel: (bootloader) console_enabled: 0 (bootloader) exec_console_unconsole: 0
A solution would be appreciated, but I am also curious why it behaves like this after a manual lock.
As suggested by @Firelord, there seems to be a solution for Windows users here: https://forums.oneplus.net/threads/important-bootloader-wont-unlock-after-relock.324398/