Develop Bugs

phone bricked? stuck at "this build is for.." screen

hi guys,
today i made a huge mistake. i was trying to deinstall the cm9 by just wiping my phone. accidentaly i made a "system wipe" with my recovery. now my phone ist stuck in the "this build is for development purposes only" screen. i tried to reboot into recovery via the aio kit - error: device not found. (led not flashing, not even when i connect it to the "normal" loading adapter). i just read another thread which ended in sending the device back to htc. i wonder if there is any possibility to safe my phone from that.
greetz bow111

Are you able to acces the Bootloader by closing the phone and restart it by keeping pressed at same time VOLUME DOWN + POWER ?
Be careful: Do NOT press volume UP!, Do not hold Volume Down for too long!
Once you are in the bootloader you should be able to:
A:Go into recovery and repair it from there in you have the ROM on your SD card.
B:If you are unable to acces recovery mode from bootloader, try to use the All In One Tool and flash the TWRP Recovery (the one in the right part of the window) also, note that there are too version, CDMA and GSM, if you have a sim card flash GSM, if you do not have a simcard use CDMA.
Let me know how it went

rzarectha said:
Are you able to acces the Bootloader by closing the phone and restart it by keeping pressed at same time VOLUME DOWN + POWER ?
Be careful: Do NOT press volume UP!, Do not hold Volume Down for too long!
Once you are in the bootloader you should be able to:
A:Go into recovery and repair it from there in you have the ROM on your SD card.
B:If you are unable to acces recovery mode from bootloader, try to use the All In One Tool and flash the TWRP Recovery (the one in the right part of the window) also, note that there are too version, CDMA and GSM, if you have a sim card flash GSM, if you do not have a simcard use CDMA.
Let me know how it went
Click to expand...
Click to collapse
ok. my phone just quick restarted. it directly went back to the "htc quietly brilliant" screen. pressing volume down + power button for a few seconds doesnt work to get into bootloader. i tried it serveral times. im not even able to turn the phone off. holding the power button only wont help at all.
thanks for ur help.
edit: i feel.. pranked now it worked and i went from bootloader to recovery (twrp already installed). can u tell me what to do now? thanks a lot already

Hm,
Well since you cant remove the battery on this phone, id suggest to just let it finish with what it has left off of the battery. once it is closed try to recharge it and then try to boot in recovery, ofc you might not be able to do this today, depends how much battery you had left when the problem started, but it's a chance, also if it's rooted you bootloader will be unlocked so i doubt HTC will grant you warranty for it (not 100% about this though). let us know if you manage to do any progress with it after you manage to make it close.
cheers

rzarectha said:
Hm,
Well since you cant remove the battery on this phone, id suggest to just let it finish with what it has left off of the battery. once it is closed try to recharge it and then try to boot in recovery, ofc you might not be able to do this today, depends how much battery you had left when the problem started, but it's a chance, also if it's rooted you bootloader will be unlocked so i doubt HTC will grant you warranty for it (not 100% about this though). let us know if you manage to do any progress with it after you manage to make it close.
cheers
Click to expand...
Click to collapse
i just edited my post. managed to get into recovery (twrp). what do i have to do now?

Download a new rom and transfer it to your sd card, then flash it from your recovery.

If u have the ROM in the SD card just flash it and reboot other wise as he mentioned above
Sent from my One V using xda premium

Ok, last night i went to sleep.
You now need to find a way to put a ROM on your SD card. whatever ROM you choose make sure you have the correct kernel for it (in every post for ROMs you will find a download link to the correct kernel aswell).
So what you do now (after you have the ROM .zip file on your SD card and your Kernel file in your PC) is:
-Put your phone into Bootloader, Select fast boot and connect the USB cable, and make sure it tells on your phone "FASTBOOT USB"
-Then in All in One select "Flash Kernel" and browse to the correct Kernel, and flash it.
-Reboot your phone in Recovery mode, you have the option in the fastboot screen.
-In the Recovery menu select Factory Reset -> Wipe System.
-While still in recovery go to "Install update from SD card" (or something similar) and choose the ROM .zip file, wait for it to be flashed
-reboot your phone (1st boot is always a bit slower, could take up to 5 minutes).
-after you get to your main screen, reboot the phone again and flash a Google Apps (gapps) .zip file. You will find the correct version from your ROM in the official thread of the ROM. You DO NOT run a factory reset, wipe system or anything like that for flashing Gapps.
Good luck.

got my phone working again. additionally i tried to "re-stock" my phone via a ruu.exe. now i have a new problem ( -.- ;D). my phone wont connect to wlan. it always hangs on "authenticating with wifi (dont know if translated it the right way)". some has an idea how to solve that problem?
p.s. sry for answering this late. had to do a lot of stuff for my finals :/
edit: was a problem with my router

flash a proper kernel
Sent from my One V

[Q] phone crashed last night, now says it needs to be activated, wont activate

Hoping someone here can give me some help. Sometime last night my phone crashed - had an error message on the screen asking me if i wanted to restart - basically the android version of a blue screen.
I rebooted and when it started up it tried to activate but failed. Tried it a few times, never activated. I called sprint and they had me type in 2 different codes:
##72786# which didn't get an error but didn't help anything
They had me try a 2nd 6 digit number, which I'm not sure if it's unique to my phone or not so I wont post it here but that did nothing at all - typed in the ##______# and nothing happened. They claimed it was because the phone is rooted, but the phone is ONLY rooted. I haven't installed a new OS it's the stock rom as far as i can tell.
Anyone have any ideas whats going wrong here or how to fix it?
thanks
edit: and apparently now I wiped the OS from the phone since it wont go past the LG logo. Is there some way for me to either copy a rom onto the phone from TWRP or copy a backup onto the phone? I've got a couple of TWRP backups saved on my pc, but since the phone wont start up I don't have any way of copying them onto the phone - damn non-user removable sd cards.

merkk said:
Hoping someone here can give me some help. Sometime last night my phone crashed - had an error message on the screen asking me if i wanted to restart - basically the android version of a blue screen.
I rebooted and when it started up it tried to activate but failed. Tried it a few times, never activated. I called sprint and they had me type in 2 different codes:
##72786# which didn't get an error but didn't help anything
They had me try a 2nd 6 digit number, which I'm not sure if it's unique to my phone or not so I wont post it here but that did nothing at all - typed in the ##______# and nothing happened. They claimed it was because the phone is rooted, but the phone is ONLY rooted. I haven't installed a new OS it's the stock rom as far as i can tell.
Anyone have any ideas whats going wrong here or how to fix it?
thanks
edit: and apparently now I wiped the OS from the phone since it wont go past the LG logo. Is there some way for me to either copy a rom onto the phone from TWRP or copy a backup onto the phone? I've got a couple of TWRP backups saved on my pc, but since the phone wont start up I don't have any way of copying them onto the phone - damn non-user removable sd cards.
Click to expand...
Click to collapse
Can you boot to recovery?
If you can, then flash a newer TWRP build, they have MTP support, you can mount it while connected to your PC, copy a ROM zip over (there is a stock on in these threads somewhere), flash it from recovery, wipe everything first. Then you should be able to boot into a working device.

Yes I can boot into twrp, but I'm not sure how to copy files that way. I tried using adb but it couldnt find the phone. Can you give me some tips on how to copy a new ROM or twrp backup to the phone?
Thanks

merkk said:
Yes I can boot into twrp, but I'm not sure how to copy files that way. I tried using adb but it couldnt find the phone. Can you give me some tips on how to copy a new ROM or twrp backup to the phone?
Thanks
Click to expand...
Click to collapse
Yes, first thing is to flash this.
http://cubegamemc.de/kevinjoa/lollipop/recovery-geehrc/twrp/
You can flash it through fastboot.
follow these steps:
1. Download and place the file on your PC.
2. Reboot your device into Fastboot Mode. To do that, simply hold down the Volume DOWN+Power buttons together.
3. Once inside the Fastboot mode, connect your device to your PC via USB cable.
4. Launch a Command Prompt Window in the folder you saved the recovery image to. You can do that by holding down the Shift button on your keyboard and right-click on any blank area on the screen, then select Open command window here.
4. Enter the following command into the Command Prompt Window. You need to replace recoveryfilename.img with the actual name of the Recovery Image you downloaded.
Code:
fastboot flash recovery recoveryfilename.img
5. Once it is done, reboot your device
Code:
adb reboot recovery
should do it. If not, just hold down the power button, and get back to recovery.
at that point you should have the newest recovery. This recovery has MTP enabled so you can transfer files just like you can if you had a running device.
Once it shows up on you PC you can transfer a ROM zip or a backup to the internal SD. From there you I am sure you know how to flash a zip or restore a backup. It is the same as an older version. MTP should be under the "MOUNT" section of TWRP. I don't remember because I have a different device now.
Good luck!
If this doesn't work, follow the thread here: You would need the super big full bin file if you do though because you do not have a working ROM or zip currently on your internal SD card and this contains a very old recovery, but it does work.
http://forum.xda-developers.com/showthread.php?t=2230106
edit: I altered the directions from the source here for the att version. Don't worry, I changed them to suit your current need.
http://theunlockr.com/2013/03/26/how-to-install-twrp-recovery-on-the-lg-optimus-g-att/

My phone seems to behave a little differently than what you describe. Holding down the volume down and power button just turns it on. Holding vol up and power puts me into a screen with the android bot on it with the option to restart bootloader, go into recovery, or power off. and at the bottom there's some text indicating fastboot mode is on.
I was able to use the fastboot command to load the newer recovery. But for some reason, none of the adb commands work on my phone.
I'm copying a twrp backup to the phone now and i'll restore that. Hopefully that'll fix the issue of the phone not booting and if i am really lucky, fix the issue of the phone not being activated, but I'm not too hopeful about that.
Thanks again for all your help

hey - just wanted to say thank. Got my phone to boot back up again. Unfortunately the backup restore doesnt seem to have fixed my initial problem. Phone is back to saying it needs to be activated. Any ideas about that? It's also showing zero bars - not sure if that's what it's supposed to show when it's not activated.
Thanks again for your help

merkk said:
hey - just wanted to say thank. Got my phone to boot back up again. Unfortunately the backup restore doesnt seem to have fixed my initial problem. Phone is back to saying it needs to be activated. Any ideas about that? It's also showing zero bars - not sure if that's what it's supposed to show when it's not activated.
Thanks again for your help
Click to expand...
Click to collapse
EDIT:: TRY THIS FIRST<
Do a full wipe of the system and data, not internal. GO to recovery, select wipe, then factory reset. Then boot your phone. You will have to setup everything again but it might help. If it does not, you can always restore your backup again.
^^^^^^^^^^^^^^^^^^^^^^^
Interesting that your phone was the opposite for the buttons. Maybe I had it backwards, or maybe my source did. Either way I am glad you have a device that boots now.
Check this...
Go to the about section and see if your imei and other information are blank or have 0's. I am almost certain that there are 0000's.
If that's the case then you lost your EFS some how. and there is a way to recover that as long as you have a backup somewhere. You should have one somewhere if you used freegee to unlock your phone in the beginning. If not, perhaps an earlier backup you had of your device. A lot of the recoveries for this device make a backup of the EFS.

well i just dropped the phone off at a sprint repair store to see if they could do anything with it now that it actually boots. If they can't fix it, I'll try what you suggested. Although i already tried a factory reset and that didn't help.

well you are right about the esn/meid/IMEI - they are all zeros
I did a restore and then used freegee to restore the efs. Will free tell you if there is no backup of the EFS? Because i restored it, it finished pretty much instantly, and then i restarted the phone just be safe. Unfortunately it didn't fix it.
Phone still says searching for service, and now there's a little red x over the bars. Before the bars were blank but there was no red x. Not sure if that makes any difference.
Also, something else weird is going on now. I just tried copying a newer backup to the phone to try and restore the newer one. I don't seem to be able to copy files now. When i drag the folder windows , it says the device has stopped responding. If i try and copy each individual file in the backup folder, it starts to copy, and then just sits there like it froze, or like it's copying so slowly it might as well be frozen. I had to reflash twrp to the newer version and then I'm able to copy files.
Reloaded the efs backup again but still can't activate/have all zeros.

Weirdest issue ever seen - endless reboot to "OTA updating", stuck at 53%

I'm a computer science student, so assume me with required ability.
Also I've searched this issue for a whole afternoon, I'll list the methods that I tried below.
Environment:
M8 android 6.0, s-off, unlocked bootloader, rooted, twrp recovery
Some modification to system partition(hosts, busybox, bloatware removed)
Set-up before applying an small ota(~89mb):
Since it's a trivial update, I didn't bother reflash all the system image - and I can't find one for my country(TW)either.
I documented every change in system partition, so I did the following steps to prepare.
1. removed xposed framework
2. unrooted by supersu built-in function.
3. put deleted bloatware back to /system/app, /system/priv-app .
libRSSupport.so and librsjni.so under /system/lib/ have been modified and I don't know why - whatever, I replaced them with the stock one.
4. reflashed stock recovery
I DID NOT(forgot to) uninstall busybox and revert the changes of hosts file, if this matters.
/system/bin/app_process32, boot partion and Supersu modified files are "likely" to be restored to stock.(I have no way to confirm.)
Problem:
Applied OTA, it rebooted to a green spinning circle with progression bar- regular OTA procedure.
But, it stuck at 25% for seconds(guess it's system partition integrity check), and progressed to 53%, stuck at 53% for about 10s.
And then it rebooted, entered OTA update mode again, and so on. I STUCKED AT OTA LOOP.
Methods that I've tried:
Pressed pwr+up under light for 10+ seconds - phone won't accept power button input during OTAs.
Pressed pwr+down / down only when reboot - can't enter fastboot, still OTA updating.
Connected to PC - adb devices not found, fastboot reboot recovery no response.
The current method that I figured out:
I'd like to wait until it drained out, check if charging it shows the normal charging mini kernel.
If so, try button combination into fastboot.
Guess if xda can't help, I'll have to ask for htc... : (

Unrooting the ROM doesn't work; you need full stock ROM to OTA.
But having a non-stock (unrooted) ROM will usually result in an error, and no OTA installation. So I agree this is a big weird.
29988122 said:
Pressed pwr+up under light for 10+ seconds - phone won't accept power button input during OTAs.
Click to expand...
Click to collapse
Try holding power + vol up for 30 seconds or more; even up to a minute (if there is no change). I'm not sure if updating OTA will impact this, but that button combo will force a reboot in every other situation I've seen when the screen is on.

Quick followup:
After battery depleted and complete shut off, I tried reboot to fastboot(by pushing power+down / down only)
No avail.
Even by charging only, it would immediately enter OTA.
I guess htc's OTA would write itself into bootloader, and thus I WON'T be able to enter the normal bootloader/recovery until OTA's completed.
But in my case, OTA's got error so....I got stuck at OTA loop!
The encryption key of my sdcard(adopted storage) was still inside phone's data partition....
Do I really need to give up?
: ( ....

29988122 said:
I guess htc's OTA would write itself into bootloader, and thus I WON'T be able to enter the normal bootloader/recovery until OTA's completed.
Click to expand...
Click to collapse
What is happening, is that the bootloader is designed to automatically look for an update file and install it, before it gives you the other bootloader options.
I've seen another with the similar problem. I couldn't think of anything in that case either. You really can't do much if you can't get to fastboot or delete the OTA file (and I can't think of any way you would do either of those, that hasn't already been tried).
What happens if you remove the SD card? Does it still try to install OTA?

redpoint73 said:
What is happening, is that the bootloader is designed to automatically look for an update file and install it, before it gives you the other bootloader options.
I've seen another with the similar problem. I couldn't think of anything in that case either. You really can't do much if you can't get to fastboot or delete the OTA file (and I can't think of any way you would do either of those, that hasn't already been tried).
What happens if you remove the SD card? Does it still try to install OTA?
Click to expand...
Click to collapse
Ya, still installing OTA.
Someone has told me a way to bypass OTA, somehow it worked. I'll post it here in case someone faced the same situation as I did.
1. let it do the OTA loop until power automatically shut down.
2. take out both sim and sdcard.
3. MANUALLY boot, let it auto shut down, repeat until it can only boot for few seconds or less.
4. plug in charger, check if charging mini kernel appeared or not. If not, repeat step 3.
5. it is told that the bootloader has some kind of low battery protection mechanism that it would skip OTA's under extremely low battery condition. Therefore after 30s or a little bit more charging, pull the plug(essentially shut it down), then magically you can now boot into bootloader via pwr+down.
Of course you'll wanna charge until about 30% or more, then reflash twrp and system partition... : p
Thank you xda and redpoint73, you just made my day!

Accidently deleted Android OS on HTC One M8

I was trying to load Lineage onto an old One M8, I had just cleared the system, cache and data partitions using TWRP. I then clicked reboot, which I now realise was a mistake. I am now stuck on the HTC logo screen, none of the physical buttons are responding, so i cannot get into bootloader etc. I can't send ADB commands to it, it won't show up on windows file explorer, I can't even turn it off. As is said this is an old phone so I am not worried about losing data, which is probably just as well at this stage!
Any advice would be appreciated!

Kieran C said:
I was trying to load Lineage onto an old One M8, I had just cleared the system, cache and data partitions using TWRP. I then clicked reboot, which I now realise was a mistake. I am now stuck on the HTC logo screen, none of the physical buttons are responding, so i cannot get into bootloader etc.
Click to expand...
Click to collapse
The physical buttons will respond, but you need to hold them for a pretty long time in the current "stuck" state. Do this:
1) Hold vol up button and power button, until the phone restarts (may take about a minute in the current stuck state).
2) Once the screen goes dark to reboot (but before the HTC logo screen appears again - I think you have 5 seconds or so), let go of the buttons, and only hold the vol down button. Do not let go of vol down, until you see the bootloader screen.
3) If you fail to get to bootloader, you simply got the timing wrong. Either started pressing vol down too late, or you let go of it too early. Simply repeat steps 1 and 2, until you get to bootloader.
4) Once in bootloader, simply select recovery, which will boot TWRP. And flash Lineage as you originally intended.
A note on wiping system when flashing a ROM: I know some folks will swear by this, and some guides will tell you to do it. But it is not necessary, and as you've seen can cause some complications. Nothing that isn't easily solved, but may give you headache nonetheless (like this case here).
The ROM install script will wipe system before it installs the custom ROM. So doing it yourself is redundant. And in the case of the ROM fails to install (it happens) you are stuck without a working OS. My recommendation is only to wipe cache, Dalvik and data when flashing a custom ROM (the default wipe in TWRP).
Any perceived "benefit" from wiping system is usually a placebo. In the rare event that the custom ROM fails to boot (or some other issue), you can always go back and flash again, wiping system (as a troubleshooting measure, etc.). Of the years of flashing ROMs (dozens and dozens of times) on various Android devices, I can count maybe 2 times where I felt I needed to wipe system when flashing a custom ROM.
Kieran C said:
I can't send ADB commands to it, it won't show up on windows file explorer
Click to expand...
Click to collapse
This can be expected when "stuck" on the logo screen. adb will only work when booted to a working OS, or alternately when booted to TWRP. Same thing with MTP access (File Explorer).

My Honor 7x BND-L21 is quite broken, need help

Hello, sorry for the generic title, but i'm quite the noob about android modding and stuff.
Anyway I wanted to root my phone, just to stream some music to my stereo system. How naive I was...
So I unlocked the bootloader, installed twrp with adb and SuperSU with twrp. Everything was fine and phone was rooted but my past naive me thought "well let's try a custom rom, why not". So I went forth and downloaded some stuff from getdroidtips and what I understood is that all I needed to do was to do a wipe, then install the zip file via twrp. I did that and didn't work. After that I realized I made a crucial mistake: I didn't backup my phone from twrp, so I was there with no OS, quite panicked and frustrated. So I tried some other roms, finally I got one that worked, this: https://forum.xda-developers.com/honor-7x/development/openkirin-aosp-8-0-honor-7x-t3746257
It works but it's barebones and on boot it shows a message: "There's an internal problem with your device. Contact your manifacturer for details.". So, I tried recovering from HiSuite, recovery mode etc but nothing worked, I reinstalled SuperSU in the new OS via twrp to see if that would help somehow, but no. in the end I had the even more naive thought that maybe unrooting would allow me to repair via hi suite or something, so I mindlessly selected "complete unroot" on the SuperSU app, and this was the second big mistake, the process somehow ****ed up the twrp install and it no longer works. Instead, if I try to enter twrp with power button + volume up button, it shows the regular "your phone has been unlocked" screen and then comes up for a split second a black screen with, on the bottom half of the screen the "no command" logo, under it some lines of code that I can't read. It suddenly disappears and sometimes enters in a bootloop showing this screen and powering off every time.
If I keep power button pressed bootloop ends and the phone boots "regularly" in the openkirin OS.
I tried reinstalling twrp the same way I did the first time. No error on adb but same no command behaviour
So what I got now is:
kind of bootlooping no command window
openkirin OS with internal problem message
fastboot and rescue mode
it seems to work on adb (everything is fine if I type adb devices)
not working HiSuite recovery
not working Huawei eRecovery
not working download mode (I guess? the power+volume up+volume down combination)
Maybe I should mention I also did a data wipe (?? the option on the right next to "advanced wipe" in the Wipe screen, if I remember correctly) in twrp before installing openkirin, it was suggested on a yt video about how to install openkirin. And that, at a stage I tried using MultiTool but it gives me an error: "exception during a web client request. Error#9", while at the bottom left it says "downloading AdbWinUsbApi.dll..."
Sorry for the general noobishness and the bad english that might be there.
So, any tips for bringing back the phone to normal? Or at least repair twrp??
Please help, I hate needing to throw this phone away just because I wanted to stream some music and because of a couple of stupid errors

Sorry for not answering earlier. It seems, between TWRP and stock recovery, you have messed up I think. When there is no proper recovery it become difficult to bring back the phone. You should try to put it in fastboot mode first, by powering off, pressing the volume lower button and connecting it to computer. Try installing TWRP and flash a custom rom other than openkirin from there if possible. Fastboot is the choice to go if recovery is messed up.

sdivk said:
Sorry for not answering earlier. It seems, between TWRP and stock recovery, you have messed up I think. When there is no proper recovery it become difficult to bring back the phone. You should try to put it in fastboot mode first, by powering off, pressing the volume lower button and connecting it to computer. Try installing TWRP and flash a custom rom other than openkirin from there if possible. Fastboot is the choice to go if recovery is messed up.
Click to expand...
Click to collapse
No worries, I managed to fix it anyway. Some things might be obvious but I'll share what I did nevertheless, in case some other newbie finds himself in a similar situation.
So there was seemingly no way of reinstalling twrp nor the stock recovery. But luck came my way and by almost random clicking I found out that, even if multitool closed as soon as I clicked the ok button in the error message, if I simply ignored the error, the program worked just fine (as I write this I installed another version and it gave no error message). So I played with it a bit and found out that it can flash twrp and it does not need a file from you, it already has a twrp version ready to install. I did that and it worked. It looks like the first twrp file I used didn't work anymore or was someway corrupted by the countless things I tried. So, with twrp working again I was able to backup the sloppy openkiring OS and try the unbrick tool. So I browsed the internet for a guide. Guides always mention as the first step for unbricking using the VENDOR.img file located inside a full stock rom. Problem is, 99% of the times they provide a rom without the needed file. So after some tries I found a good complete stock rom with the VENDOR.img here: drive.google.com/file/d/1tjHefytEWbpuV1f4YjX8AaSMzT6jr8TQ/view but I can't remember which forum/site I found it in.
I followed the guide which involves:
-extracting the UPDATE.APP file contained in the provided zip with huawei extractor tool into an X folder on your pc
-copying the VENDOR.img file contained in the X folder, on the root folder of the sd card
-backing up OS (if there's any) via twrp (I had something like 50 partitions, I guess that was messing things up a bit, but for safety I backed them all up)
-doing an advanced wipe from twrp selecting ALL checkboxes BESIDES the SDcard of course
-flashing the vendor.img file via twrp selecting the "Vendor" partition when prompted
-downloading the update_full_[your model]_hw_[your region].zip file, in my case update_full_BND-L21C_hw_eu.zip
-extracting the UPDATE.APP file contained in update_full_BND-L21C_hw_eu.zip with Huawei extractor tool in some other folder Y
-looking for a file named cust.img/CUST.img/version.img/other_name.img (I don't know which other names it can have, I was lucky and had a VERSION.img file in it)
-rename the cust.img/CUST.img/version.img/other_name.img to CUST.img and copy it from the Y folder to the X folder
-boot your phone into fastboot mode
-connect phone to multitool via usb and select the "unbrick" tab
-there, Multitool asks for a folder, give it the X folder. There are some checkmarks on the Multitool "unbrick" page. 4/5 of them should become checked after the folder input. In my case the first 4
-then, simply press the unbrick button
-wait and pray (it can look like it freezes while it's copying the system.img file but wait, it'll be fine)
So I did that and it worked flawlessly, the phone booted slowly but surely into EMUI 5.1 with Android 7.0 I think and everything was fine.
At that point I had a working OS and a working twrp but wanted to go back to the OS I was used to, Android 8.something so, I tried connecting the thing to HiSuite and it automatically asked if I wanted to update, not to 8.something but to 9.1. I thought "SURE I DO!" and updated flawlessly (I thought 9.1 hadn't even been released here in Italy).
When it booted I found out the new OS was working like an antivirusless xp pc: it didn't recognise the SIM, it would crash every 20 seconds, app downloads got stuck at 99%, if it felt like it, it rebooted, pc connection was not stable. Besides, the update being "official" and installed from "trusted" sources (HiSuite), it completely wiped twrp.
And that was the "OH ****, here we go again" moment: no twrp and worse-than-ever-working OS.
So because of the new EMUI version, I guess, Multitool kept recognizing the phone but stopped offering its own recovery, eRecovery, twrp files available for flashing. I was completely frustrated with all of this and decided to give up, but I made the last effort: I tried the relock function in multitool. So I provided the key, pressed relock, waited, prayed, and finally cheered. It worked like a charm. Phone runs now on EMUI 9.1 with locked bootloader without problems. Finally
So I guess in the end I payed 4 euros for a nice update, a painful and frustrating trip into android modding and a lesson : never do android modding!
no, just kidding, don't do it just if you are a newbie AND you don't want to risk to throw the phone in the grabage.
In all other cases consider it carefully
Oh, and also, God bless the MT Team and Russia altogether!! thanks

Quite an experience. All the best. ?

Lol sounds fun. I've bricked my Huawei Mate SE/Honor 7x more times than I can count. I'm just awaiting my 9.1. I want my GPU Turbo! Is it as good as it's supposed to be?