Fabian Fischer, I know how irritating it is when the portal simply refuses to show domains that are actually there. What’s happening under the covers is a brief timeout or hiccup in the portal’s domain-metadata API especially for AzureManagedDomain or any custom domain still completing DNS validation. The good news is your email flow isn’t broken, it’s just the UI.
To unblock yourself right now, switch to the CLI so you can see and fix whatever’s stuck. First, list everything on your Email Communication resource.
az communication email domain list \
--resource-group YourResourceGroup \
--email-service-name YourEmailService
If one of your domains shows a provisioningState of Pending or Failed, kick off a fresh DNS.
az communication email domain initiate-verification \
--resource-group YourResourceGroup \
--email-service-name YourEmailService \
--domain-name contoso.com
Wait for that command to report “Succeeded,” then reload the portal. If the portal still errors after you see Succeeded everywhere, try an incognito window or clear your browser cache—those stale tokens sometimes hang onto old errors. Once the CLI tells you all domains are green, the portal will finally reflect that state. If it doesn’t, you can always fall back on the same CLI commands (or ARM templates) to manage domains reliably until the UI issue is fully resolved.
Hope it helps!
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