FRITZ!Box 6490 Service - Knowledge Base
Cordless telephone is deregistered after a FRITZ!Box restart
After the FRITZ!Box is restarted, for example after a FRITZ!OS update, a cordless telephone from another manufacturer no longer connects to the FRITZ!Box automatically and must be registered again.
- The cordless telephone does not support the expanded security functions for the DECT connection.
Disabling expanded security functions
- Click "DECT" in the FRITZ!Box user interface.
- Click "Base Station" in the "DECT" menu.
- Disable the expanded security functions in the "Security" section.
- Click "Apply" to save the settings.
After disabling the expanded security functions, you must register your cordless telephone with the FRITZ!Box once.