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2017-07-29 01:51 PM
Following steps given in https://developer.sonymobile.com/unlockbootloader/
I got this response from Xperia M4 Aqua with Android Marshmallow v6:
D:\Android\android-sdk-windows\platform-tools>fastboot -i 0x0fce oem unlock 0x0123456789ABCDEF ... FAILED (remote: Command did not succeed) finished. total time: 0.170s
Would someone please instruct how should I resolve the issue?
2017-08-20 02:15 PM
You are on Windows.
Did you install the USB driver? If yes, did you start your device in fastboot mode (plug in USB cable into PC, while device is powered off, press volume_up key and plug in the USB cable into phone jack, wait till led light changes to blue, release volume_up key).
Do you see your device when you try "fastboot devices" on command line?
2017-08-21 01:12 PM
I can only think at some issues:
1. The device is/was SIM locked - in this case it can not be unlocked
2. Your sw is too old - please update to 26.3.A.1.33 software since i just tested that this version can be unlocked