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Cannot enable DECT Eco function

For technical reasons, the "DECT Eco" function is not available if a smart home device (for example FRITZ!DECT 200), a FRITZ!DECT Repeater 100, or a FRITZ!Box in DECT repeater mode is registered with the FRITZ!Box.

Note:If you are no longer using the above-mentioned devices, you can delete them under "Home Network > Smart Home" or "DECT > DECT Monitor" in the FRITZ!Box user interface.