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Knowledge document #1264
FRITZ!Box 5490
This support document is available for the following products:

Cannot register a FRITZ!DECT socket

Registration of the outlet switch, for example FRITZ!DECT 200, fails. After the automatic configuration, the "DECT" LED flashes continuously and the DECT connection between FRITZ!Box and FRITZ!DECT is not established.

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 Maximum number has been reached

You can register up to ten FRITZ!DECT devices (for example FRITZ!DECT 200) with the FRITZ!Box. If you already registered ten devices, you cannot register any more devices.

Note:Registering a FRITZ!DECT does not reduce the number of other DECT devices that can be registered.

2 Disabling the keylock

  1. Click "System" in the FRITZ!Box user interface.
  2. Click "Buttons and LEDs" in the "System" menu.
  3. Click on the "Keylock" tab.
  4. Disable the "Buttons locked" checkbox.
  5. Click "Apply" to save the settings.

3 Disabling "Reduce DECT field strength"

  1. Click "Telephony" in the FRITZ!Box user interface.
  2. Click "DECT" in the "Telephony" menu.
  3. Disable the option "Reduce DECT field strength" in the section "Radio Field Strength".
  4. Click "Apply" to save the settings.

4 Disabling "DECT Eco"

  1. Click "Telephony" in the FRITZ!Box user interface.
  2. Click "DECT" in the "Telephony" menu.
  3. Disable the option "DECT Eco" in the section "Radio Field Strength".
  4. Click "Apply" to save the settings.

5 Enabling encryption

  1. Click "Telephony" in the FRITZ!Box user interface.
  2. Click "DECT" in the "Telephony" menu.
  3. Enable the option "Permit only secure DECT connections (recommended)" in the section "Security".
  4. Click "Apply" to save the settings.
  5. If the option was disabled, you must then restart the FRITZ!Box once using the user interface ("System > Backup > Restart").

6 Re-registering FRITZ!DECT

Deregistering FRITZ!DECT

  1. Push the "DECT" button on FRITZ!DECT and hold it down for at least 6 seconds.

The "DECT" LED starts to flash as soon as the FRITZ!DECT is deregistered.

Restarting the FRITZ!Box

  1. Click "System" in the FRITZ!Box user interface.
  2. Click "Backup" in the "System" menu.
  3. Click on the "Restart" tab.
  4. Click the "Restart" button.

Registering FRITZ!DECT

  1. Plug the FRITZ!DECT into a power outlet near the FRITZ!Box.
  2. Click "Smart Home" in the FRITZ!Box user interface.
  3. Click "Device Management" in the "Smart Home" menu.
  4. Click the "Register Device" button.
  5. Within 2 minutes: Push the "DECT" button on FRITZ!DECT. Hold down the button for at least 6 seconds until the "DECT" LED starts to flash rapidly. The FRITZ!DECT is in registration mode as long as the LED flashes rapidly.

The "DECT" LED on the FRITZ!DECT remains lit as soon as the DECT connection has been established. Then you can plug the FRITZ!DECT in wherever you want; you can configure and operate it in the "Smart Home" area of the FRITZ!Box user interface.