Can't unlock xperia Z2

[FireStarterXIII]

I'm following website instructions and get this

C:\Program Files (x86)\Minimal ADB and Fastboot>fastboot devices
CB5A1Y68L2      fastboot

C:\Program Files (x86)\Minimal ADB and Fastboot>fastboot -i 0x0fce oem unlock 0x<UNLOCK_CODE>
...
FAILED (remote: Command not allowed)
finished. total time: 0.006s

 Any ideas, checked drivers and everything works fine - it looks that phone doesn't allow me to perform this action 

FW 17.1.1.A.0.438

Model D6503

[Uliwooly]

What are you trying to do?

unlock the phone from a network

or 

unlock the bootloader?

[Thommo]

That command is to unlock the bootloader but there is no unlock code entered - It's been copied and pasted - So where it says

0x<UNLOCK_CODE>

You would need to enter but not this key (That is an example)

fastboot.exe -i 0x0fce oem unlock 0x1A778D2353F13C00

Edit:

Have you check you can unlock your bootloader and also have you obtained your unique unlock key

[FireStarterXIII]

Yes I followed the instruction - unlock code is fine I just erased it due to security reasons

In general I wopuld like to put my phone into recovery mode and I can't unlock it.

[Thommo]

There isn't a recovery mode - Normally you would unlock your bootloader and root then due to having root install a custom recovery like for example ClockWorkMod, Philz Touch or TeamWin recovery - Have you enable USB Debugging via developer options

[FireStarterXIII]

I have followed all instructions from below site

http://developer.sonymobile.com/unlockbootloader/

- Debug mode ON

- SDK installed 

- Drivers installed (run in Win 8.1 x64 with drivers signature check disabled in OS)

- Fastboot devices - recognizes phone

I have checked everything and doesn't work, I have no more ideas

[Thommo]

Ah SDK had issues myself untill I installed the modified driver via device manager - Maybe this site will help on how to enter fastboot and use a command prompt

[xxxxxxxxxx]

I have same problem with xperiaz1 i can do everything root install dual recovery when i get to install cyanogenmod 12 it ddint boot .

The prob seems bootloader locked but with flashtool i do unlock and lock but cant fastboot it gives same error as urs when i wont to flash boot .

still dint find any solution .i am able to goes back to inst5all stock room but not others.i dont know where is prob DRM keys ??

sending 'boot' (12860 KB)...
OKAY [ 0.405s]
writing 'boot'...
FAILED (remote: Command not allowed)
finished. total time: 0.408s

to unlock i choose this form aslo for u will goes right.

go to C:\Flashtool\custom\mydevices\BH9078NX06\ulcode.txt             create this file inside put hte unlock code only.

Flashmode automaticly will unlock ..try this it work theorically but for me practically doesnt work stll get prob writing bootloader even from unlock