xs4all voip with Fritz!Box equipment: do not combine Fritz!Box “With prefix” number formats with xs4all “Block international numbers”: it will block non-international numbers too.
Posted by jpluimers on 2021/03/22
If you use xs4all VoIP from any Fritz!Box device, then keep the “Telephone Number Format” for “Country code” on “No”, and “Area code” to “None”:
If you have changed these to “With prefix” like I did:
combined with VoIP settings to block international numbers on the right, then when you dial a number outside your area, you will get a friendly voice telling you “this number is blocked”
–jeroen
The Wiert Corner - irregular stream of stuff 
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