With a locked bootloader on an SE ST17i running the rooted Stock Xperia Gingerbread 2.3.4, can I flash the CyanogenMod 9 onto it? Or do I really need my bootloader unlocked? I also have ClockWorkMod installed and as far as I know that shouldn't have been possible with a locked bootloader so I'm rather confused. I'm not at all experienced with rooting and I'd consider myself on just the "beginnner" stage.

I'm not too keen on the thought of unlocking my phone's bootloader as that wil most certainly void my warranty.

  • Just be cautious of flashing Sony handsets - bootloader and recovery are on the one partition thus making it difficult to upgrade! Just don't ask me why they made that awful decision! You can re-lock the bootloader again after - FYI!
    – t0mm13b
    Aug 7, 2012 at 14:51

2 Answers 2


Basically, this could be possible. I've got CM7.2 on my Motorola Droid2, which also has its bootloader locked. Being at work, I cannot access all ressources (firewall restricts me) -- but just in case, there seems to be a youtube tutorial on Unlock any Sony Ericsson Xperia in 5 minutes, just in case you want to unlock first (which should make things easier).

According to XDA your device should be supported by CM9. However, I could not figure out whether CM by default uses 2nd init on the XPeria devices (which is what must be done when the bootloader is locked -- and how it works e.g. on the Motorola Milestone 2; but obviously this is not done for the ST17i). So if you want to try with your bootloader locked, you should check with the instructions coming with your CM9 build to make sure: Some sources I've found (not sure which XPeria the ST17i is, so they might apply or not), as e.g. How to pgrade Xperia X8 to Android 4.0 ICS / How to Upgrade Xperia X8 to Android 4.1 Jelly Bean and especially Android Forums - View Single Post - All Xperia mini (un)rooting,un(re)locking bootloader,flashing CM,kernels,CWM,ROM's,tweaks etc (which explicitly applies to your ST17i), mention an unlocked bootloader as pre-condition for flashing CM9.

So the answer is probably NO, though it would theoretically be possible.

  • You definitely need to unlock the bootloader - am afraid! That is a precursor to enable flashing custom ROMs. No buts, no ifs! Just a PITA in having to do that stage but then again the principle of locked bootloader is not just for warranty, its also for when the handset gets stolen and some savvy person can unlock the bootloader which factory resets everything so contacts/messages etc are wiped clean!
    – t0mm13b
    Aug 7, 2012 at 14:55
  • @t0mm13b as I wrote above: My Moto Droid 2 still has its bootloader locked -- but at the same time runs CyanogenMod. There is a way around it, using "2nd init", but this approach is only used if unlocking the bootloader is not possible (see RootzWiki), and so far seems to be used with Motorola devices only.
    – Izzy
    Aug 7, 2012 at 15:11
  • Its motorola specific - that 2nd init yeah? Well it worked for you but the OP is talking about Sony....
    – t0mm13b
    Aug 7, 2012 at 15:20
  • Exactly -- and I mentioned this in my answer :) I was just addressing your generic "[unlocking] is a precursor to enable flashing custom ROMs. No buts, no ifs!" :P
    – Izzy
    Aug 7, 2012 at 15:27

It's not necessary. If your Xperia's bootloader is locked you can't install a custom kernel but you can install a custom ROM. I have MIUI with a stock 4.0.4 based kernel on my Xperia S.

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .