Via [WayBack] This was well hidden outside the regular Anrdoid settings I was trying at first. You need to start with the stock Android phone app, then go to settings… – Jeroen Wiert Pluimers – Google+.
The steps are in the images below, starting from the stock Android phone dialing app.
It helped solving this problem:
@jpluimers: A friend of mine cannot receive anonymous calls: his #OnePlusOne on @KPNwebcare with latest Android available for it does not ring, not even in safe mode. But calls do appear in recent calls list. This used to work in the past months ago. Any tips?
@KPNwebcare: I suggest he try his SIM-card in a different phone to determine if the problem persists. This helps us figure out if the problem is related to the or our network. If the problem remains then I recommend that your friend contacts us directly!
@jpluimers: OK. I will assist him doing this. Thanks!
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@jpluimers: Thanks for the offer. Enjoy your weekend. Somehow it’s the device. To be continued…
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@jpluimers: After trying to reset many individual settings, the only thing that worked was a complete phone reset then restore apps from backup. Of course not all apps backup just as well, but that got us 90% with only 10% of manual configuration left. Phew (: And thanks for helping us out.
–jeroen