Unlocking the bootloader on NTT Docomo devices is frequently blocked, as the carrier often requests that manufacturers permanently disable this feature. While SIM unlocking is officially supported, bypassing the bootloader lock requires checking specific eligibility for Xperia or Galaxy models and often necessitates specialized exploits. For more details on the official Sony process, visit Sony Developer World Sailfish OS Forum How to unlock bootloader | Developer World
Before attempting any software installation, you must verify if your specific Docomo-branded device even permits a bootloader unlock. For many popular Docomo devices (especially Sony Xperia), the bootloader is by the carrier. docomo unlock bootloader install
Prerequisites