Line protector is an equipment managed by NTT, and you cannot remove the protector on your own.
If line protector is determined as the cause of ADSL connection failure, you can request NTT for a replacement (replacement charge will be billed). Please note that you cannot directly ask NTT for a replacement. If you wish for a replacement, please contact Asahi Net from the contact page below. >> English Customer Support
Example of line protector being the cause of ADSL connection failure: Problem occurs when the model of the line protector is 6PTVer1 (family-type line protector for detached house or mansion).
Please connect to the internet by connecting the modular connector and the ADSL modem directly (without using splitter). Try to make a call to your landline from mobile phone, etc. while you are connected. If the line always gets disconnected, the line protector may highly be the cause.