Android 6.x unlocking by cable notice
There are various models most commonly the SM-G900W8 that currently can't be unlocked directly via our software and a cable if you are on Android 6.x.
Samsung made some changes to the bootloader and the direct unlocking isn't taking effect. It looks like an actual bug in the firmware or it could be a new security play from Samsung as well.. for now there is no cable unlock solution in the world that has a solution and neither do we.
The only solution for this problem is to downgrade your firmware to 5.x, then unlock the phone and then you can upgrade to 6.x again no problem. The phone will stay unlocked.
Downgrading from 6.x to 5.x is no problem you can just flash a 5.x firmware using the Odin software.
You can find 5.x firmware files at our friends from Samsung-updates.com. Note that flashing a phone is a bit more advanced, so if you have any doubts or question please contact our support FIRST before doing anything.