image showing what typical malicious phone calls are made of

We at NTT DOCOMO have been advising our customers not to call back a number in the received call history from an unknown number, which when called back, the caller is connected to "dating" site advertisements or adult content guide, otherwise known as "one-ring" calls. In addition, we also have been advising you not to call back with your caller ID since this will leave your number in the malicious content provider's call record and may lead to unexpected trouble. In order for our customers to use our services more safely, we have taken the following steps against "one-ring" calls.

Measure No.1 - We are now offering a Malicious Caller Block function

By registering the number you believe to be a malicious (one-ring) caller through the steps below, calls from the registered landline telephone number will be blocked.

notice Immediately responding to the recorded guidance will accrue charges on the registered number (malicious caller).

Instructions (up to 19 numbers can be registered)

1. First, activate the "Malicious Caller Block Function".

step1

2. Register the telephone number to be blocked.

notice After you have activated the function through step 1 above, additional numbers can be registered by proceeding directly to step 2.

step2

notice (Example screen) Registering 03-XXXX-XXXX as *01.

  • notice Cannot be used simultaneously with One-Touch Dialing.
  • notice In order to switch back to the One-Touch Dialing function from the "Malicious Caller Block Function", register your home phone number or a valid number other than 9999 as 0*00 to deactivate the "Malicious Caller Block Function." This will also result in the deletion of all numbers registered in "Malicious Caller Block Function" numbers *01 through *19.
  • notice Since registered numbers cannot be checked afterwards, we suggest you keep a record of the registered numbers. Also, please be careful not to register different numbers by mistake.
  • notice Regular landline telephone numbers can be registered with this function, whereas mobile phone numbers cannot be registered (mobile phone numbers cannot be blocked).
  • notice Not compatible with FOMA, Pre-Call and PHS.

Measure No.2 - Use a ringing melody with a silent beginning

We are providing some ringing tones where the first 2 to 6 seconds are silent. These ringing tones can be downloaded free of information charges from the "DOCOMO Home Page" in the i-mode Menu.

How to access

image showing the different steps that one needs to take through the Japanese i-mode menu to access the right page

notice i-mode compatible terminals (excluding all 501i series models and NM502i)

Measure No.3 - Use the step-tone function

If your mobile phone has a step-tone that starts silently, we recommend that you use this feature (step-tone is a function that the ringing melody gradually becomes louder).

  • notice Step-tones that start silently, step-tones and downloading of ringing melodies may not be available on all models. Please refer to your manual for details.
  • notice There will be a received call history even if you cannot hear the ringing melody. We advise you not to call back unknown numbers.

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