(Almost) bricked Oneplus X: cannot unlock bootloader, cannot install OS

[Japeroen]

Hi all,

 

tl;dr: Tried to hard unbrick my Oneplus X, which was partly succesful (no OS is installed in the process, while there should be). I am now stuck with no OS and only the Oneplus recovery. I want to install an OS, but it says my bootloader is locked. To unlock it, I need an OS ==> vicious circle.

 

Full story below:

Recently I've decided to reinstall LineageOS on my Oneplus X because I had quite some problems with it (battery drain, apps crashing, wifi slow to connect, ...). I've done it like 5 times before on this device for various reasons, so I didn't expect any problems. I had LineageOS 14.1 and TWRP 3.0.3 installed. When I wiped everything, I wanted to flash the ROM I had ready using TWRP. However, gave an error number 7, saying that the ROM is not compatible for the device, which I am sure was. Remembering I had a similar issue a while back, I installed flashed an updated version of TWRP (3.2.2) using TWRP itself. That was successfull, but here's where the trouble began. 

 

I noticed that TWRP didn't recognise any storage (Internal storage, SD card and USB-OTG all showed up as 0 MB) any longer. Neither could I mount any of the storages. I've tried a lot of things to solve this. After a while, I decided that the only hope left was the 'mega unbrick guide' (https://forums.oneplus.com/threads/guide-mega-unbrick-guide-for-a-hard-bricked-oneplus-x.417648/) which claims to be able to recover any device, unless it has a hardware problem. I got good hope as I got near the end of the guide. The last step says 'Disconnect phone from PC and boot into system', but here I got stuck on the Oneplus boot logo, making me think that there is no OS installed on the device. 

 

I can still access the recovery using power button and volume down, but the recovery that the mega unbrick guide installs, is the limited Oneplus recovery. It allows to install a ROM from the local storage, or from USB using adb sideload. When I try option 1, nothing happens, no new screen opens or anything. When I try option 2, I enter the adb sideload mode which would normally allow me to sideload a ROM using my pc. My pc confirms I'm in adb sideload mode, and I try to sideload a ROM. It starts fine, but after a few seconds, it says 'Installation failed'. I've tried stock OOS, latest OOS as well as LineageOS 14.1 that was installed before.

 

Another thing that I can do in the Oneplus recovery is rebooting into fastboot mode, where I should be able to flash the recovery of my choice. Again, my phone confirms I'm in fastboot mode and I try to flash or boot TWRP recovery, but I get the message: 'FAILED (remote: Device not unlocked cannot flash or erase)'. Okay, seems like the bootloader is still locked, so I should just go and unlock it using 'fastboot oem unlock'. This gives the message: 'FAILED (remote: oem unlock is disabled)'. I've been searching around a lot on the internet, and it seems like the only way to enable oem unlock, is in the OS itself in the developer settings. But the problem is, I have no OS and cannot install one because the bootloader is not unlocked... So I'm stuck in this vicious circle.

 

I've been searching on the internet for hours and starting to lose hope. At this point, I would be happy if I can just have any OS (OxygenOS or LineageOS or something else) running. If I have that, I should be able to take it from there.

 

Any help is much appreciated. Thank you very much.

 

Kind regards,
Jeroen

[Japeroen]

Update:

Oneplus support could solve the problem for me! Or at least, partly. It appears that Oneplus has an updated version of the tool used in the mega unbrick guide: MSMDownloadTool V2.1 instead of V2.0. This tool did it's job perfectly, OOS was also installed, in contrast to V2.0 of the tool. I ****ed it up again after that (oops), but found the tool V2.1 online here (https://github.com/finlayacourt/Oneplus-X-Recovery). Some files are missing here like the system.img, but I just copied them from the folder of tool V2.0 found in the mega unbrick guide. It didn't work as perfectly as Oneplus's tool, but at least I was able to install OOS from the Oneplus bootloader, which I wasn't able to before. So knowing that, in the end, the result is the same as for their tool. A working OS again, perfect! So now I can unlock the bootloader again and continue the adventure.

Now, what I've found is that the mainboard I have on my OPX is a newer version (if you search on Google for 'oneplus E1003_15', you'll find some things about it, not much though). I'm 99% positive that this caused all the problems I've encountered. It is why TWRP couldn't see any storage, why the stock Oneplus recovery couldn't see any storage, why the tool V2.0 didn't work and why V2.1 did work. If I wanted a working TWRP, I had to install a modified version of TWRP which is compatible with the newer version, from here: https://www.android-hilfe.de/forum/c...-x.867374.html (yes, once you're relying on German sites, you know you went very deep). After that, I could install LineageOS 14.1 again. I was unable to install the unofficial LineageOS 15.1 however, but knowing where I came from, what I've gone through and how much time I've lost on all of this, I think I'll just stick with LineageOS 14.1 until this baby can retire... 

Got to say I only have very positive experiences with Oneplus and it's customer support, and this only adds to it! 

I hope I can also help other people with the same problem. :)