A locked bootloader generally means that you would not be able to install customized software into your Android gear.
The ASUS ZenFone 2 was once upon a time a part of that list but not anymore.
Check out the source link below for full instructions.
However, he also suggests to back up data in the event something that is not expected happens.
So, before you try this on your ASUS ZenFone 2 ensure that your data is secure.
How to unlock bootloader:
1.
Update to 2.19.402. root it3.
confirm adb is insatlled and working4.
c’mon visit the XDA Forum link for more information.
SOURCE:XDA
Read More
source: www.techworm.net