Buying a Xperia z1compact

[senortech]

Hello can any one help. How can I purchase a z1compact from eBay with a unlockable boot loader. What am I looking for? eg. an international version, or one from a specific region. I have one already but the bootloader unlock allowed =no. It is rooted and I have twrp recovery but I want to upgrade or flash a android 7.0 custom rom .Any solutions for that. I don't want to end up with two phones with seem problem.

 

[115ek]

Hello can any one help. How can I purchase a z1compact from eBay with a unlockable boot loader. What am I looking for? eg. an international version, or one from a specific region. I have one already but the bootloader unlock allowed =no. It is rooted and I have twrp recovery but I want to upgrade or flash a android 7.0 custom rom .Any solutions for that. I don't want to end up with two phones with seem problem.

I can't answer your question directly. It's more an alternative solution which I think should work (at least you can try...).

If you've got a working TWRP you should be fine. Installing AICP/lineage/whatever shouldn't be a problem then, even with a locked BL.
Just boot to TWRP, wipe /data, /system and caches and install the firmware you'd like to have.
Only downside: If something breaks and you can't even enter TWRP you have to use the sony repair/flashtool and reinstall stock. Then repeat the rooting + TWRP installing stuff...
Make sure you've installed a recent (and working) TWRP version as for installing ROM's starting from oreo you need at least TWRP 3.2.x if I remember correctly.

BTW: Why do you want to install 7.0 / nougat? It's outdated and not updated anymore. I'd suggest using android 9

• AICP 14
  
• LineageOS 16

or android 8

• LineageOS 15.1

or even android 5

• LineageOS 12.1

These builds are updated at least monthly. And the first three of them also provide OTA update support which makes things very comfortable.

 

[senortech]

Thanks so much for your reply. Although I'll say it left me surprised. After researching the last couple of days ,even here on this site I was lead to believe that an unlocked bootloader was absolutely essential to flash a custom rom not based on stock firmware much less upgrade to a later version of android. However I am more than willing to take your word for it seeing that you are one of the modders for the Rom I would like to try "LoS 15 Oreo". I fully understand that the risk is totally mine. A further question, I currently run andriod 5.1.1 with dual custom recovery twrp and cwm, how do I update my current twrp version 2 . Something to the latest recommended. Do I flash the new zip with my current twrp recovery ?

 

[115ek]

Thanks so much for your reply. Although I'll say it left me surprised. After researching the last couple of days ,even here on this site I was lead to believe that an unlocked bootloader was absolutely essential to flash a custom rom not based on stock firmware much less upgrade to a later version of android. However I am more than willing to take your word for it seeing that you are one of the modders for the Rom I would like to try "LoS 15 Oreo". I fully understand that the risk is totally mine. A further question, I currently run andriod 5.1.1 with dual custom recovery twrp and cwm, how do I update my current twrp version 2 . Something to the latest recommended. Do I flash the new zip with my current twrp recovery ?

Well, at first I have to apologize for the "optimistic" answer. There's one "small" detail I forgot about. It's the boot.img signature which may cause problems. However I don't know if Sony was enforcing the verified boot / signature checking even with android L. This would mean the bootloader checks, if the boot.img was signed with Sony keys - if not: it'll enter a bootloop (or doesn't turn on at all). Unlocking the bootloader then allows you to also boot unsigned images.
But I didn't tried booting custom images with locked BL on my own
So I guess it's a try and error thing here... Most likely you'll end up unsuccessfully

However you can still give it a try. Can you post the output of

cat /proc/partitions

when you're in recovery? (TWRP has an inbuilt terminal, or you can use adb shell).
At first you need an independent recovery - which means it can boot up without needing the stock boot.img. That's your current configuration: original sony kernel boots up and you decide which ramdisk it should load by pressing vol+/-.
That's why it's actually no real recovery. If something in boot.img breaks you won't be able to reach recovery anymore.
So I think of following steps now:

1. Make sure you've installed the latest sony firmware
2. install the bootloader patch from @munjeni (he also states you need a unlockes BL, so it's not really promising Maybe he can jump in and give further clarification here?)
3. install TWRP (e.g. this) with dd like this (change your inputfile accordingly):
   

   dd if=/sdcard/twrp.img of=/dev/block/platform/msm_sdcc.1/by-name/FOTAKernel

4. if you strike it lucky you'll be able to boot into the new real recovery with: poweroff device; hold VOL down and power until vibration; release power but keep holding VOL down until TWRP screen comes up (needs ~10 seconds or so)

To be honest: I lost my confidence a bit. Maybe buying a device with unlockable BL is the way to go. I suppose the devices sold with contracts by big carriers like Vodafone or Telekom (however they are called in your country) DON'T have unlockable BL's. So devices without a simlock may have a good chance to be unlockable. However - that's just a guess.

 

[JIJOK]

Well doing some research found an interesting Movistar forum stuff : if you unlock your phone ( free to use whatever SIM you want ) then its possible to change "bootloader allowed : no to yes" . At least thats what the spanish thread says ( https://comunidad.movistar.es/t5/So...not-allowed/m-p/2404928/highlight/true#M26138 )
1- After make your phone SIMfree it says to do a factory reset and check if allowed : yes
2- Also says that you need to send phone to sony tech fisic store
3- Or using Sony pc companion
I am not sure why it says that need to deliver the phone to sony store since online bootloader is kids game, but thats what the thread says

Finally, if you want to buy a new one, all unlocked phones ( no carrier ) will let you unlock bootloader ...... 99% sure :fingers-crossed:

ps : my english is horrible, I hope you understand it