Docomo requests manufacturers to strictly lock bootloaders to secure mobile payment systems (Osaifu-Keitai), digital TV tuners (OneSeg/Seg), and DRM-protected content.
| Problem | Cause | Fix | |---------|-------|-----| | oem unlock not allowed | Carrier locked bootloader | Cannot unlock. No fix. | | remote: Command not allowed | Fastboot commands restricted | Use official method (if exists) | | Device not recognized in fastboot | Driver issue | Install Google USB driver / Sony fastboot driver | | Unlock code invalid | Wrong IMEI or model excluded | Check Sony’s website again or use different code |
, or are you checking if a device you're planning to buy can be modded? docomo unlock bootloader top
: This is what our guide focuses on. It's a much deeper level of unlocking that gives you administrative control over the device's software. While NTT Docomo has a policy for SIM unlocking, it has a very different stance on bootloader unlocking: it is not officially supported . In fact, the majority of Docomo-branded smartphones have the bootloader unlock flag set to no from the factory. You can check your own device's status by opening the dialer, typing *#*#7378423#*#* , and navigating to Service info → Configuration → Rooting Status .
If you want the top reliability without risking a $500 brick, Japanese repair shops like or Janpara (and some online services) offer paid bootloader unlocking. | | remote: Command not allowed | Fastboot
Before wasting time downloading developer tools, check if your specific phone has a permanent hardware or carrier lock. The process varies slightly depending on your manufacturer. For Docomo Sony Xperia Devices
If you manage to bypass the lock using an exploit, be aware of the following: While NTT Docomo has a policy for SIM
Docomo SIM unlocks phones after 100 days. That has nothing to do with bootloader unlocking. Many users confuse this.
Unlocking usually voids any remaining warranty.
ここまで見てきたように、方法は存在しますが、決して安全な遊びではありません。以下のリスクを理解した上で、で行うことが絶対条件です。
NTT Docomo is Japan's largest mobile service provider. Unlike global variants of popular phones from Sony, Samsung, and Sharp, Docomo requests manufacturers to hard-lock the bootloader. Why Docomo Locks Devices