What do the FRITZ!Box error messages mean?

Overview of the most common FRITZ!Box error messages during sipgate registration with explanations and solution suggestions.

If registering the sipgate data in your FRITZ!Box does not work or calls are rejected, you can find the exact error message in the FRITZ!Box under settings, then System, Events and then under Telephony.

Error message 401: SIP ID, SIP password and/or SIP server data incorrect

Exception: IPv6 - Hitron modem - FRITZ!Box

\ Problem: Hitron does not forward the 401 requests correctly to the FRITZ!Box\ Solution: Convert Hitron to bridge mode

Error message 403: server data incorrect

Settings - Telephony - Own phone numbers - edit sipgate: other provider select Registrar: sipgate.de Proxy server: sipgate.de Save changes and check registration

Error message 404: destination number dialed incorrectly or FRITZ!Box dials incorrectly

Settings - Telephony - Own phone numbers - edit sipgate: other provider select Registrar: sipgate.de Proxy server: sipgate.de Automatic prefixes: 49, 0, 00, XXX do not tick any of them Save changes and call the destination number again.

Alternatively depending on the firmware: Settings - Telephony - Own phone numbers - connection settings: Country: Germany Country code: leave blank / leave blank Area code: leave blank / leave blank Save changes and make an outgoing call. If everything works, you can activate the automatic prefix in the sipgate account - Settings - Telephony

Error message 408: Timeout

Settings - Telephony - Internet telephony/Own phone numbers - Advanced settings/connection settings: Keep port forwarding of the internet router for internet telephony active: enable Keep port forwarding active every: 30 seconds

If a router is used before the FRITZ!Box:

• in the 1st router enable UPnP and check registration

• in the 2nd router disable UPnP and Port forwarding set up: 5060/UDP to the IP of the FRITZ!Box and 7078-7085/UDP to the IP of the FRITZ!Box

If a FRITZ!Box is used as the first router, set up the SIP data in the first router. For AMV, see the following instructions: Register a FRITZ!Box on a FRITZ!Box with SIP registrar to make calls through it.

Error message 480: Stun server entered incorrectly, call barring, error in the phone, or DND/reject active on the phone

settings - Telephony - Own phone numbers - edit sipgate: other provider select proxy: sipgate.de registrar: sipgate.de Stun server: leave blank if visible Save changes. Test an incoming call.

Call barring may be active and should be disabled: Link to AVM: Call barring

Disconnect the telephone from the FRITZ!Box and call in. If the FRITZ!Box rings, you know the error comes from the phone. On the phone, you can activate DND/reject. All incoming calls are rejected.

Error message 488: Not acceptable here

- Either an audio codec is being used that we do not support, or there is too little bandwidth available for the currently configured audio codec - You need at least 100 kbit/s download and upload - FRITZ!Box - Settings - System - View: enable expert view - settings - Connections - Own phone numbers - edit sipgate Provider: other provider Enable: provider requires G.726 according to RFC 3551

Error message: timeout, no response

Variant 1: 1.) Activate expert view in the FRITZ!Box (System - View - check) 2.) In menu Settings - Telephony - switch to Internet telephony/Own phone numbers 3.) Tab Advanced settings/connection; here additional connection for internet telephony via DSL (PVC) disable (remove check mark) Variant 2: 1.) Activate expert view in the FRITZ!Box (System - View - check) 2.) In menu Settings - Telephony - switch to Internet telephony/Own phone numbers - edit sipgate 3.) Always register via an Internet connection enable/check 4.) Save changes and check registration If variants 1 or 2 do not help, it can be assumed that you have received a FRITZ!Box with its own firmware from your DSL provider/cable provider instead of AVM firmware. Third-party providers such as sipgate are actively blocked in the FRITZ!Box. Solution: None known, as you are usually not allowed to install the AVM firmware because it is a loan/rental device. Alternatively: Use VoIP telephones or a VoIP analog adapter + analog telephone, then the FRITZ!Box only acts as a router without telephony.

Error message: DNS error

FRITZ!Box - Settings - Telephony - Own phone numbers - edit sipgate: Provider: other provider User name: SIP ID Password: SIP password Registrar: sipgate.de Proxy: 217.10.79.9 Now save the entered data.

Does the error message "DNS error" still appear for both proxy IP addresses? Then it is likely that special firmware from your provider is installed on your FRITZ!Box and the FRITZ!Box cannot be used as a VoIP router with third-party providers such as sipgate.\

Note: Alternatively, you can then use your FRITZ!Box as a router without VoIP with sipgate by - using a VoIP phone, - a VoIP adapter with an analog telephone - or a VoIP software solution behind the FRITZ!Box.