Phone system issue.

Brass Contributor

Hi All.... I am hoping someone can set me on the correct path.  I am trying to configure a pstn gateway to our SBC but powershell is telling me that the domain is not configured for the tenant.. I have confirmed that the domain is indeed set up in the 'domains' settings although it is not the default domain.


Here is the command used:


 New-CsOnlinePSTNGateway -Fqdn -SipSignallingPort 5061 -MaxConcurrentSessions 10 -ForwardCallHistory $true -Enabled $true


Here is what i get:


Can not use the "" domain as it was not configured for this tenant.
+ CategoryInfo : InvalidArgument: (Fqdn=SBC1.vcsho...des=408,503,504:TrunkConfig) [New-CsOnlinePSTNGateway], ArgumentException
+ FullyQualifiedErrorId : CustomValidationFailed,Microsoft.Rtc.Management.Internal.NewOnlinePSTNGatewayCmdlet
+ PSComputerName :



Can someone please point me in the right direction... i'm starting to lose hair....  Thanks

6 Replies

So the domain is verified?
Have you created any users with the UPN set to this domain?

yes the domain has been verified, but there are errors that i am waiting for our provider to resolve. Is it likely to be the fact that there are errors in the DNS settings is causing the issue? the usernames were initially  the standard .onmicrosoft ones but i added this domain and set as primary thinking this would work.  we have no on premise solution for o365 it is all through the cloud...

Sounds it could be a dns issue then! Go to ”domains” in the admin portal, select your custom domain and verify the dns records there and see what’s missing!

To follow up on Adam have you added the as a sub domain under the main domain within the tenant? You should be able to do this if you have verified the main domain. It is recommended that both should have the correct DNS records on them so the setup on both of them is fully completed.

Best, Chris
Sbc1 is a hostname right?
Hmm yeah, it’s just the error being thrown is referring to sbc1.vcshosted as a domain. In an standard office 365 environment that would be added as a subdomain of unless it is being used for multiple tenants.

AFAIK, and I know this article refers to multiple tenants, that there ought to be a subdomain in the tenant for

Just wanted to check that aspect was correct as it may be causing the error. A check on MX Toolbox can’t find any validation TXT’s on that subdomain.

Best, Chris