- Joined
- Oct 9, 2019
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- 44
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3CX 16 SP5 on Windows 10. 3CX is sending calls to one extension directly to voicemail.
Two devices: a Yealink T42S desk phone and an iPhone 3CX app.
Extension shows Available.
DND on the Yealink is Off (confirmed in the phone's web UI).
3CX verbose logging says the extension is treated as Busy because it's in DND mode:
07/31/2020 5:02:59 PM - Call(C:10): from L:10.1[Extn:250] has failed, because Extn:101 is in DND mode
07/31/2020 5:02:59 PM - [CM503016]: Call(C:10): Attempt to reach <sip:[email protected]:5060> from Extn:250 has failed. Reason: Busy
In a packet trace, I don't even see an INVITE going to the phone. How/why does 3CX think it's in DND state? I don't see that reported in REGISTER either.
Phone reboot and server reboot didn't help.
Considering replacing the physical phone.
An hour and a half later, I found this post where JohnS_3CX suggests dialing *60 to disable DND. That Dial Code is not documented (https://www.3cx.com/docs/pbx-dial-codes/), but I tried it and it fixed it. I also found I could toggle it on with *61.
So do *61 and *60 control a server-side DND that does not appear on any phone, app, web client, or management UI? Or is the phone DND button supposed to be toggling that?
I realize there is some legacy functionality here, but if this really is a completely hidden DND, I'm wondering if I should just blank out the SETAWAY parameter to avoid issues if someone accidentally dials *61? (I learned later that the user had been trying to dial the U.S. standard *67 to block outbound caller ID.)

Thanks,
Two devices: a Yealink T42S desk phone and an iPhone 3CX app.
Extension shows Available.
DND on the Yealink is Off (confirmed in the phone's web UI).
3CX verbose logging says the extension is treated as Busy because it's in DND mode:
07/31/2020 5:02:59 PM - Call(C:10): from L:10.1[Extn:250] has failed, because Extn:101 is in DND mode
07/31/2020 5:02:59 PM - [CM503016]: Call(C:10): Attempt to reach <sip:[email protected]:5060> from Extn:250 has failed. Reason: Busy
In a packet trace, I don't even see an INVITE going to the phone. How/why does 3CX think it's in DND state? I don't see that reported in REGISTER either.
Phone reboot and server reboot didn't help.
Considering replacing the physical phone.
An hour and a half later, I found this post where JohnS_3CX suggests dialing *60 to disable DND. That Dial Code is not documented (https://www.3cx.com/docs/pbx-dial-codes/), but I tried it and it fixed it. I also found I could toggle it on with *61.
So do *61 and *60 control a server-side DND that does not appear on any phone, app, web client, or management UI? Or is the phone DND button supposed to be toggling that?
I realize there is some legacy functionality here, but if this really is a completely hidden DND, I'm wondering if I should just blank out the SETAWAY parameter to avoid issues if someone accidentally dials *61? (I learned later that the user had been trying to dial the U.S. standard *67 to block outbound caller ID.)
Thanks,