Hi guys,
I am seeking help. I had an unlocked bootloader for a while and then relocked it via flashtool. Now I would like to unlock it again, but flashtool throws errors on me:
- Command not succeeded or Failed: Device is rooted already
I do not have root (checked with root checker), and the .ftf firmware I have flashed was .108 Generic Europe.
Any ideas what's going on?
maxld said:
Hi guys,
I am seeking help. I had an unlocked bootloader for a while and then relocked it via flashtool. Now I would like to unlock it again, but flashtool throws errors on me:
- Command not succeeded or Failed: Device is rooted already
I do not have root (checked with root checker), and the .ftf firmware I have flashed was .108 Generic Europe.
Any ideas what's going on?
Click to expand...
Click to collapse
How did you backup your TA Partition?
A few months ago, I had the very same issue. However I never used flashtool to relock my bootloader.
For me, I am in the belief that I had an issue with TA Backup 9.10, as after I restored my TA Partition via TA Backup 9.10 from a backup made from the same version I would be faced with the same error. As I had previous used TA Backup 9.9 to backup my TA Partition, I tried that version with the backup it had made, and I was able to unlock my bootloader again.
Summary
Using TA Backup version 9.10 to backup my TA Partition and then restore it to relock the bootloader resulted in Command not succeeded or Failed: Device is rooted already. When trying to re-unlock my bootloader.
Using TA Backup version 9.9 to backup my TA Partition and then restore it to relock the bootloader, Fastboot was able to unlock my bootloader again.
Thanks for a suggestion. However I managed to unlock it with a different method.
In the flashtool folder, check if
[FLASHTOOL FOLDER]/custom/mydevices/[DEVICE SERIAL]/ulcode.txt
exists.
If not, create the folders along the way there and then use notepad or something very lightweight to create the ulcode.txt. Put in the code, be sure to enter the code without the 0x, so just the code as it came from Sony. Save the file and start FlashTool.
Cheers.
maxld said:
Thanks for a suggestion. However I managed to unlock it with a different method.
In the flashtool folder, check if
[FLASHTOOL FOLDER]/custom/mydevices/[DEVICE SERIAL]/ulcode.txt
exists.
If not, create the folders along the way there and then use notepad or something very lightweight to create the ulcode.txt. Put in the code, be sure to enter the code without the 0x, so just the code as it came from Sony. Save the file and start FlashTool.
Cheers.
Click to expand...
Click to collapse
Can you mark the topic with [solved], this is one post we need to keep so we can find
blueether said:
Can you mark the topic with [solved], this is one post we need to keep so we can find
Click to expand...
Click to collapse
Sure, but how (lol). When I edit my first post, I can't change the topic.
Edit: thanks wedgess.
Related
[Q] Downgrade from .244 to 307
Hi Folks
I've just updated my tablet to the 10.3.1.A.0.244 and i didn't knew it wasn't rootable, I feel like an idiot.
So now i want to downgrade to .307 wich can be root and then update it to .244.
I spotted this tuto [FTF][4.2.2] Xperia Tablet Z (SGP321) 10.3.1.A.0.244 Global Unbranded but i'm not quite sure about some of the steps.
How can i flash the .307 firmware with flashtool if my tablet isn't bl unlocked?
How after flashing the .244 firmware back can i boot my tablet from a boot.img?
And finaly does the backup TA method really relock the bl as it was prior bl unlock?
Thank you in advance for you help!
satanluimm said:
Hi Folks
I've just updated my tablet to the 10.3.1.A.0.244 and i didn't knew it wasn't rootable, I feel like an idiot.
So now i want to downgrade to .307 wich can be root and then update it to .244.
I spotted this tuto [FTF][4.2.2] Xperia Tablet Z (SGP321) 10.3.1.A.0.244 Global Unbranded but i'm not quite sure about some of the steps.
How can i flash the .307 firmware with flashtool if my tablet isn't bl unlocked?
How after flashing the .244 firmware back can i boot my tablet from a boot.img?
And finaly does the backup TA method really relock the bl as it was prior bl unlock?
Thank you in advance for you help!
Click to expand...
Click to collapse
I followed the steps in the thread you mentioned and successfully backed up my TA partition, unlocked my bootloader, rooted .244 and restored DRM keys & re-locked bootloader ... It too me some time but it did all work.
Got it but...
b8drf said:
I followed the steps in the thread you mentioned and successfully backed up my TA partition, unlocked my bootloader, rooted .244 and restored DRM keys & re-locked bootloader ... It too me some time but it did all work.
Click to expand...
Click to collapse
Thanks for your reply mate!
Can you tell me wich partitions you excluded in flashtool? which checkbox you checked?
i was so eager to gain root access in order to remove all the bloatware that i couldn't wait to try and finaly i did it but once finished my device was stuck in a bootloop^^
I had to update it via sony update tool to get it back.
At first i excluded everything except the system partition and i also unchecked wipe data, it didn't work...
Then i added baseband cause i assumed it was linked to the firmware and that was why it failed, wasn't it either...
I have an unknown partition which i don't what it's used for^^ and also a partition named partition ( the internal memory?).
FOTA and TA i can guess.
satanluimm said:
Thanks for your reply mate!
Can you tell me wich partitions you excluded in flashtool? which checkbox you checked?
i was so eager to gain root access in order to remove all the bloatware that i couldn't wait to try and finaly i did it but once finished my device was stuck in a bootloop^^
I had to update it via sony update tool to get it back.
At first i excluded everything except the system partition and i also unchecked wipe data, it didn't work...
Then i added baseband cause i assumed it was linked to the firmware and that was why it failed, wasn't it either...
I have an unknown partition which i don't what it's used for^^ and also a partition named partition ( the internal memory?).
FOTA and TA i can guess.
Click to expand...
Click to collapse
I simply followed the instructions in the thread ...
So just to be clear
So just to be clear, you lunched flashtool you click flash, selected the flasmode method then selected the 307 firmware in the list ( where did you dowloaded the 307 firmware??
i founded it on this thread [FTF] SGP321 10.1.1.A.1.307 Unbranded)
Then what did u do? Just click flash and nothing else?
I don't see any particular directives except flash 307^^
satanluimm said:
So just to be clear, you lunched flashtool you click flash, selected the flasmode method then selected the 307 firmware in the list ( where did you dowloaded the 307 firmware??
i founded it on this thread [FTF] SGP321 10.1.1.A.1.307 Unbranded)
Then what did u do? Just click flash and nothing else?
Click to expand...
Click to collapse
Correct and that is the link where I downloaded the .307 firmware from - just make sure you check the md5's after download - also make sure you have the tablet in Flashmode (FlashTool will tell you if it is in Flashmode or Fastboot)
hth.
b8drf said:
Correct and that is the link where I downloaded the .307 firmware from - just make sure you check the md5's after download - also make sure you have the tablet in Flashmode (FlashTool will tell you if it is in Flashmode or Fastboot)
hth.
Click to expand...
Click to collapse
I'm confused about that cause on the BACKUP TA thread it says you cannot flash someone elses ta partition...
I'll try it
satanluimm said:
I'm confused about that cause on the BACKUP TA thread it says you cannot flash someone elses ta partition...
I'll try it
Click to expand...
Click to collapse
That isn't a TA partition, that is a copy of the .307 unbranded firmware (.ftf file)
The TA partition backup is later in the instructions and you are correct, you have to restore your own TA backup as they are tied to the individual phone.
To be honest, and please take this the way it was intended, by the types of questions you are asking it would appear that this is all very new to you - please proceed at you own risk as I cannot help much further as I simply followed the instructions in the original post.
hth.
New to the tablet z for sure i've had several abdroid devices sony htc samsung, never had any problems but with this one i'm king of very cautious..
Makes me Wonder why^^
Flashed it works but i don't want to unlock the bl since i need to enter my imei on sony's website and that mate voids the garanty^^
I will stay on .307 until a root procedure comes up for .244
Many thanks for your time!
satanluimm said:
New to the tablet z for sure i've had several abdroid devices sony htc samsung, never had any problems but with this one i'm king of very cautious..
Makes me Wonder why^^
Flashed it works but i don't want to unlock the bl since i need to enter my imei on sony's website and that mate voids the garanty^^
I will stay on .307 until a root procedure comes up for .244
Many thanks for your time!
Click to expand...
Click to collapse
Yes, I thought that as well re: IMEI, but simply requesting an unlock code via the Sony site doesn't mean you actually went thru with the unlock process - as long as your tablet is showing the correct Rooting status = "Bootloader unlock allowed: Yes" then they have no proof that you followed thru with the unlock ...
I understand your caution though ...
hth.
Hello dear XDA Community,
- Xperia Z Ultra
- 4.4.2
- 14.3.A.0.681
- C6833
I have a big problem with understanding all of this tutorials. I read everything about rooting and unlocking the Bootloader.
I understood that I need to backup my TA Partition for Unlocking my Bootloader so I can continue to use Sony technology.
Requirements ? Root. Okay that was my first problem. So i looked up how to root my phone and what do i need ? A phone with a unlocked bootloader. great! Sure you can say "look at this topic and carefully read" but I really did that and I am really helpless. Thanks for any help!
What did I read ?
- http://forum.xda-developers.com/showthread.php?t=2292598&nocache=1 (requires root)
- http://forum.xda-developers.com/showthread.php?t=2569904 (requires unlocked bootloader)
- watched severel youtube videos and encountered the same problem
Greets
tr0teK
When your bootloader is unlocked, you can never use X-Reality and any other item which requires the DRM in the Trim Area partition,
Restoring the TA partition without relocking the bootloader will not result in the return of X-Reality and such even if you are using a Sony ROM. This situation appears to have changed since the release of 4.4.
Backing up the TA partition is only good for relocking the bootloader on a Stock ROM (any custom AOSP, CM, AOSPA etc will fail to boot on a locked bootloader), for personal choice or returning the phone under warranty.
You can unlock the bootloader when not rooted, in fact you don't do it with the phone running normally anyway so root or not rooted, it does not matter in that sense.
You don't need to unlock the bootloader to root, if you are willing to re-set up your phone again. What you need to do is downgrade to 4.2, which is rootable, root, install recovery and flash the 681 pre-rooted zip, and use flashtool to flash the associated ftf file to get rooted on 681.
Follow the instructions in Lord Manhattan's thread that you linked to,in order to downgrade and install a recovery, then visit the following link to get the zip & ftf to re-up to 4.4 (681). You most likely will lose cellular connectivity whilst you are downgraded (there is a way around this, but as you are only going down to 4.2 to get a recovery, maintaining your IMEI for that short period of time is just a waste of effort), but it will return when you are back on 681 (4.4).
http://forum.xda-developers.com/showthread.php?t=2687848
- Downgrade to 532
- Root it using Bin4ry's tool
- Backup the TA partition
- Unlock bootloader
- Either update to 681 again and take it from there or flash a kernel with recovery/TWRP and flash a pre-rooted 681. It's easy to root 681, so whatever floats your boat.
Don't mean to hijack this topic but I don't want to open another thread,
if I back up the TA partition, unlock bootloader, root the phone, then relock bootloader, then restore TA partition to bring back the xreality,
I am not going to install custom recovery and Roms.
Thanks for the Informations. I will give it a try the next days and report you if it worked.
coolmingli said:
Don't mean to hijack this topic but I don't want to open another thread,
if I back up the TA partition, unlock bootloader, root the phone, then relock bootloader, then restore TA partition to bring back the xreality,
I am not going to install custom recovery and Roms.
Click to expand...
Click to collapse
Technically it'll work, but i have never done it before. Everything should go smoothly until you're going to re-lock the bootloader. You can't re-lock it on a custom kernel, and you'll be on a custom kernel once you flash Jackie's kernel with recovery, so you'll have to flash a complete stock kernel, then restore the TA partition with the TA Backup Tool, which will also automatically re-lock the bootloader. You should in theory end up with a complete stock ROM with root. That's on paper.
Worst case scenario? If you re-lock the bootloader while you're on a custom kernel, it'll explode it won't power on at all, and all you'll get is a blinking red LED and death. To fix this, just unlock the bootloader in Flashtool again and you're back to start again. It's not dangerous, but it's nerve wrecking to see it there, just blinking without any sign of life. I almost crapped my pants the first time i experienced it, and had no clue what was happening or what to do.
LordManhattan said:
Technically it'll work, but i have never done it before. Everything should go smoothly until you're going to re-lock the bootloader. You can't re-lock it on a custom kernel, and you'll be on a custom kernel once you flash Jackie's kernel with recovery, so you'll have to flash a complete stock kernel, then restore the TA partition with the TA Backup Tool, which will also automatically re-lock the bootloader. You should in theory end up with a complete stock ROM with root. That's on paper.
Worst case scenario? If you re-lock the bootloader while you're on a custom kernel, it'll explode it won't power on at all, and all you'll get is a blinking red LED and death. To fix this, just unlock the bootloader in Flashtool again and you're back to start again. It's not dangerous, but it's nerve wrecking to see it there, just blinking without any sign of life. I almost crapped my pants the first time i experienced it, and had no clue what was happening or what to do.
Click to expand...
Click to collapse
Thanks for the reply, I think I will ditch rooting from this phone, too much troubles, I don't understand why Sony put the DRM key in a trim partition, perhaps they don't want us to root the phone after all.
I did it guys. It worked!
My steps:
- Downgraded to 4.2.2 with Flashtool (.532)
- Rooted with Bin4ry's tool
- Installed CWM and TWRP Dual Recovery for Xperia Z locked Bootloader by krabappe12548
- Flashed to 4.4.2[rooted] (http://forum.xda-developers.com/showthread.php?t=2687848)
Now I have the newest version with Root Access. Everything works great
Greets
tr0teK
tr0teK said:
I did it guys. It worked!
My steps:
- Downgraded to 4.2.2 with Flashtool (.532)
- Rooted with Bin4ry's tool
- Installed CWM and TWRP Dual Recovery for Xperia Z locked Bootloader by krabappe12548
- Flashed to 4.4.2[rooted] (http://forum.xda-developers.com/showthread.php?t=2687848)
Now I have the newest version with Root Access. Everything works great
Greets
tr0teK
Click to expand...
Click to collapse
is this witout unlock the bootloader?
MjsNL said:
is this witout unlock the bootloader?
Click to expand...
Click to collapse
Yep, that will work well on a locked BL
If you are only downgrading to flash the current rooted firmware, you don't even need to root 532, as [nut]'s dual recovery can be installed by the same method that bin4ry's root is delivered, just install the recovery, flash the zip, flash the ftf and away you go
I will soon be getting a new Z Ultra and I would like to know what to do:
I want to stay on the stock rom but root it and update it to the latest version
So should I downgrade/root/unlock bootloader/whatever before i start using it?
If so, can someone tell me the steps to doing it e.g.
1) downgrade to .623
2) unlock bootloader
3) flash kernel and recovery
4) backup TA
5) update to latest version
6) root
???
panyan said:
I will soon be getting a new Z Ultra and I would like to know what to do:
I want to stay on the stock rom but root it and update it to the latest version
So should I downgrade/root/unlock bootloader/whatever before i start using it?
If so, can someone tell me the steps to doing it e.g.
1) downgrade to .623
2) unlock bootloader
3) flash kernel and recovery
4) backup TA
5) update to latest version
6) root
???
Click to expand...
Click to collapse
If all you are wanting is latest firmware with root just let it update then follow this thread.
http://forum.xda-developers.com/showthread.php?t=2784900
If you do decide to unlock bootloader then you have listed steps in wrong order.
1. Root
2. Backup TA
3. Unlock Bootloader
Alternately you could use the dualrecovery installer for step 1 as it has the root exploit built in.
adfurgerson said:
If all you are wanting is latest firmware with root just let it update then follow this thread.
http://forum.xda-developers.com/showthread.php?t=2784900
If you do decide to unlock bootloader then you have listed steps in wrong order.
1. Root
2. Backup TA
3. Unlock Bootloader
Alternately you could use the dualrecovery installer for step 1 as it has the root exploit built in.
Click to expand...
Click to collapse
I would like to have recovery installed and have a backup of my TA partition just in case
Can you tell me the whole process please?
1-> ?
panyan said:
I would like to have recovery installed and have a backup of my TA partition just in case
Can you tell me the whole process please?
1-> ?
Click to expand...
Click to collapse
1.http://forum.xda-developers.com/xpe...de-root-android-4-4-4-ver-14-4-0-108-t2801587
2.http://forum.xda-developers.com/showthread.php?t=2292598
Backing up TA needs to be done before unlocking bootloader as that is when DRM keys become lost. Also want to mention that I made a Nandroid right after using dualrecovery installer and before unlocking bootloader. When that backup was restored my bootloader became locked again, but I can't swear that the DRM keys remained intact.
adfurgerson said:
If all you are wanting is latest firmware with root just let it update then follow this thread.
http://forum.xda-developers.com/showthread.php?t=2784900
If you do decide to unlock bootloader then you have listed steps in wrong order.
1. Root
2. Backup TA
3. Unlock Bootloader
Alternately you could use the dualrecovery installer for step 1 as it has the root exploit built in.
Click to expand...
Click to collapse
adfurgerson said:
1.http://forum.xda-developers.com/xpe...de-root-android-4-4-4-ver-14-4-0-108-t2801587
2.http://forum.xda-developers.com/showthread.php?t=2292598
Click to expand...
Click to collapse
So the whole process would be:
1) root (http://forum.xda-developers.com/xpe...de-root-android-4-4-4-ver-14-4-0-108-t2801587)
2) backup TA (http://forum.xda-developers.com/showthread.php?t=2292598)
3) unlock bootloader?
4) flash recovery
5) update to latest version OS
6) root
?
panyan said:
So the whole process would be:
1) root (http://forum.xda-developers.com/xpe...de-root-android-4-4-4-ver-14-4-0-108-t2801587)
2) backup TA (http://forum.xda-developers.com/showthread.php?t=2292598)
3) unlock bootloader?
4) flash recovery
5) update to latest version OS
6) root
?
Click to expand...
Click to collapse
Sorry I am at work so my simple replies are even worse than normal.
The easyroot method (towelroot) and the dualrecovery exploit don't require downgrading, so just let it update to latest firmware. If you can't get the OTA for any reason you can flash the latest FTF for your region with flashtool. Then once on latest use dualrecovery installer and TA backup tool. That should have you rooted with recovery and backed up.
Edit...unlocking bootloader is only needed to flash custom ROMs or kernels.
adfurgerson said:
Sorry I am at work so my simple replies are even worse than normal.
The easyroot method (towelroot) and the dualrecovery exploit don't require downgrading, so just let it update to latest firmware. If you can't get the OTA for any reason you can flash the latest FTF for your region with flashtool. Then once on latest use dualrecovery installer and TA backup tool. That should have you rooted with recovery and backed up.
Edit...unlocking bootloader is only needed to flash custom ROMs or kernels.
Click to expand...
Click to collapse
Dont apologise, I really appreciate your help.
I will want to flash custom roms in the future so should I unlock it on day 1?
So the process is:
1) update to latest 4.4.4
2) install dual recovery from here: http://forum.xda-developers.com/showthread.php?t=2647492
3) go into recovery and make a backup
4) make a TA backup with this: http://forum.xda-developers.com/showthread.php?t=2292598
5) root with this: http://forum.xda-developers.com/showthread.php?t=2784900
panyan said:
Dont apologise, I really appreciate your help.
I will want to flash custom roms in the future so should I unlock it on day 1?
So the process is:
1) update to latest 4.4.4
2) install dual recovery from here: http://forum.xda-developers.com/showthread.php?t=2647492
3) go into recovery and make a backup
4) make a TA backup with this: http://forum.xda-developers.com/showthread.php?t=2292598
5) root with this: http://forum.xda-developers.com/showthread.php?t=2784900
Click to expand...
Click to collapse
Step 5 shouldn't be needed as the dualrecovery will take care of rooting. I didn't check the links you posted but if they are the same as I did you should be good.
adfurgerson said:
Step 5 shouldn't be needed as the dualrecovery will take care of rooting. I didn't check the links you posted but if they are the same as I did you should be good.
Click to expand...
Click to collapse
Ok, excellent
What would the process be if I wanted to unlock the bootloader too?
panyan said:
Ok, excellent
What would the process be if I wanted to unlock the bootloader too?
Click to expand...
Click to collapse
Here is a quick rundown....TA backup needs root to work, TA backup saves DRM keys needed for Sony proprietary stuff like audio, video and camera, also if warranty replacement is needed. DRM keys are lost when bootloader is unlocked, also internal storage is wiped. If unlocking a brand new phone then nothings lost, but if you have apps, pics, etc. then you will need to back them up first. I can't remember if I needed to rerun the dualrecovery after unlocking or if recovery was intact. I do know that restoring a Nandroid that I made before unlocking bootloader to phone after it was unlocked caused a soft brick until I unlocked it again. Maybe @blueether could double-check the info I have given you for accuracy as I may be over my head here.
adfurgerson said:
Here is a quick rundown....TA backup needs root to work, TA backup saves DRM keys needed for Sony proprietary stuff like audio, video and camera, also if warranty replacement is needed. DRM keys are lost when bootloader is unlocked, also internal storage is wiped. If unlocking a brand new phone then nothings lost only the DRM keys are lost, but if you have apps, pics, etc. then you will need to back them up first. I can't remember if I needed to rerun the dualrecovery after unlocking or if recovery was intact. I do know that restoring a Nandroid that I made before unlocking bootloader to phone after it was unlocked caused a soft brick until I unlocked it again. Maybe @blueether could double-check the info I have given you for accuracy as I may be over my head here.
Click to expand...
Click to collapse
It all looks about right, I would just change the above a little
blueether said:
It all looks about right, I would just change the above a little
Click to expand...
Click to collapse
Will root and recovery persist after unlocking bootloader? I can't remember if it does or not. Thanks for looking that over, the last I want is to give out erroneous advice.
adfurgerson said:
Will root and recovery persist after unlocking bootloader? I can't remember if it does or not. Thanks for looking that over, the last I want is to give out erroneous advice.
Click to expand...
Click to collapse
I cant unforget either, been too long since I've had a locked BL
1) update to latest 4.4.4 - See FTF thread
2) install dual recovery by [NUT]
3) go into recovery and make a backup - handy if you ever need to get back to stock - I'm not sure if it backs up the TA either
4) make a TA backup and save it on the cloud and on HDD
5) unlock the BL by visiting Sony's dev site and using flashtool
6) re-root / reinstall su if needed
7) make another backup of the TA and call this one unlocked - this can then be used to unlock the BL with out the data wipe
All off the top of my head and not done in ages
blueether said:
1) update to latest 4.4.4 - See FTF thread
2) install dual recovery by [NUT]
3) go into recovery and make a backup - handy if you ever need to get back to stock - I'm not sure if it backs up the TA either
4) make a TA backup and save it on the cloud and on HDD
5) unlock the BL by visiting Sony's dev site and using flashtool
6) re-root / reinstall su if needed
7) make another backup of the TA and call this one unlocked - this can then be used to unlock the BL with out the data wipe
Click to expand...
Click to collapse
Brilliant - thank you very much
You guys have been invaluable!
Hi,
I get a new XZ1c,
what must I do now to get TA backup, root (magisk ?), recovery (trwp?)
must I unlock bootloader ?
best seems to follow https://forum.xda-developers.com/xperia-xz1/development/kernel-sony-xz1-23-january-2018-t3739586
but what to do before ?
janjan said:
Unlock bootloader
- A Working TWRP-with latest patch security
Click to expand...
Click to collapse
edit 47.1.a.12.270
thanks
hazote said:
Hi,
I get a new XZ1c,
what must I do now to get TA backup, root (magisk ?), recovery (trwp?)
must I unlock bootloader ?
best seems to follow https://forum.xda-developers.com/xperia-xz1/development/kernel-sony-xz1-23-january-2018-t3739586
but what to do before ?
edit 47.1.a.12.270
thanks
Click to expand...
Click to collapse
Not possible to backup TA after unlocking bootloader.
U need to unlock your device bootloader first. Then find custom twrp for your device and flash that. Finally flash my kernel to fix picture issue.
janjan said:
Not possible to backup TA after unlocking bootloader.
U need to unlock your device bootloader first. Then find custom twrp for your device and flash that. Finally flash my kernel to fix picture issue.
Click to expand...
Click to collapse
can I backup TA before ?
There is no way to backup TA partition for now.
ok thanks all.
perhaps I will wait a little before rooting my phone
So I rooted this phone 1 or 2 years ago and now I want to give this phone to my uncle. I read on some other sites to remove the root you just have to delete some folders etc and you're good. I did that but twrp is still on the phone.
I want to make it so the phone is no longer rooted and relock the bootloader so that it doesn't have the "do not trust this device" message on it
The build number it has installed is 34.4.A.2.85
hello. I'm XP docomo user here. let me tell you about my experience here. my bootloader unlock allowed was initially no. i backed up my ta partition before i force my bootloader allow to be yes. it was a successful attempt and i went straight unlocking my bootloader. then i attempted to flash back my ta for fun. the bootloader was automatically locked and the allow was no again. twrp recovery also gone lol. i don't know whether this will okay for you
the main point is backup your ta partition before unlocking the bootloader. it has drm keys which really vital to xperia camera as well as x reality mode/ super vivid. once you unlocked the bootloader, the drm keys will be gone for good unless you've it backed up.
i think restoring the ta partition which is created before unlock is the best way to relock the bootloader again.
first restore the ta partition, download latest firmware on xperifirm, use flashtool to flash ftf created by xperifirm. then, voila.
friendly reminder, flash only ftf supported for your variant. (eg. flash only f8131 ftf for f8131, SO-04H ftf for SO-04H, etc)
DO NOT ATTEMPT TO FLASH OTHER PERSON'S TA PARTITION OR YOU WILL GET ETERNITY HARD BRICK
If you didn't back up your TA partition, you can NOT unlock, as the previous poster said, trying to flash one from a different device will irrecoverably brick your one.
You can flash stock with Flashtool (the one by Androxyde, not Sony Flash Tool, they are different) though. While at it, you might give SailfishOS and Ubuntu Touch (alternative, Linux-based OSes) a shot.