I have xperia Z1 4.3 .136
I previously unlocked it successfully on .290 stock kernel using "fastboot.exe -i 0x0fce oem unlock 0xKEY" then I relocked it using flashtool BLU button then I updated the phone software using PC Companion because my xperia didn't boot after relocking..
now I'm on 14.2.A.1.136 without root and I tried to unlock BL as the official way put I failed !!
FAILED (remote: command did not succeed)
and If i tried the command again it says your device already rooted !!
tried also to unlock BL using flashtool but I failed again !!
I'm sure about drivers are installed and working.. I tried two laptops.. tried windows 7 and windows 8.1
I tried to choice the fastmode driver manually by choosing Sony sa0109 adb also failed !!
also tried minimal ADB and Fastboot but nothing works !!
and I tried to flash cwm recovery but I failed
I want to unlock my BL because I want to regain root again and I already lost my TA partition without backup.. and I prefer unlocking method because I don't like to downgrade and flashing kernels to gain root again