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Wrong outgoing call number is used for some calls

Sometimes the outgoing call number you configured in the FRITZ!Box for a telephone is not the number it uses for making calls. Individual calls are made from the landline instead of via internet telephony (VoIP), for example.

Note:All instructions on configuration and settings given in this guide refer to the latest FRITZ!OS for the FRITZ!Box.

Simply proceed as described below. After each measure, check whether the problem is solved.

1 Using a different outgoing call number to call back

If you missed a call and want to use the FRITZ!Fon's call list to return the call, the FRITZ!Fon uses the number that to call back. However, you can use a different outgoing call number to call back:

  1. Press the "Menu" key on the telephone.
  2. Scroll to "Settings" and press "OK".
  3. "Telephony" > "OK" > "Telephone no." > "OK"
  4. Select the desired outgoing telephone number.
  5. Click "OK" to save the setting.

Now the telephone number is shown in the display of the telephone and will be used as the outgoing call number for the next call.

2 Deleting dialing rules

Dialing rules may have been configured in the FRITZ!Box that force the call to be made using a different outgoing call number. Edit or delete all unsuitable dialing rules:

  1. Click "Telephony" in the FRITZ!Box user interface.
  2. Click "Call Handling" in the "Telephony" menu.
  3. Click on the "Dialing Rules" tab.
  4. Delete all of the dialing rules you want to change.
  5. Reconfigure the desired dialing rules.

3 Disabling substitute connection

When the function "Use substitute connection" is enabled, the FRITZ!Box automatically attempts to use a different number to make the call if is not possible to do so using an internet telephone number. You hear an acoustic signal (two short tones and one long one) in the telephone if the call is made using a landline number. If a different internet telephone number is used for the call, you do not hear an acoustic signal. You can disable this function in the FRITZ!Box:

  1. Click "Telephony" in the FRITZ!Box user interface.
  2. Click "Telephone Numbers" in the "Telephony" menu.
  3. Click on the "Line Settings" tab.
  4. Disable the option "Use substitute connection".
  5. Click "Apply" to save the settings.