Azure Communication Services
An Azure communication platform for deploying applications across devices and platforms.
Email Communication Services SDK suddenly deadlocks any and all Email send requests.
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Lucas Harskamp
20
Reputation points
We've been using Azure Communication Services for a while now for our Email/SMS needs without issue. However, suddenly as of last night, sending an email through the SDK (whether locally debugging in Visual Studio or running from a pod in AKS) causes the whole application to deadlock (not just the thread the email was send from).
It doesn't matter if it's the synchronous or async function (or ConfigureAwait true/false, wrapping in Task.Run, etc) is used, it always deadlocks, whereas prior it didn't.
EmailClient.Send
// or
EmailClient.SendAsync
We've tried upgrading our NuGet package from 1.0.1 to 1.1.0, but that didn't resolve the issue either. What can cause this? Has there been recent maintenance on the service, or is it tied to email limits?
Azure Communication Services
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Suchitra Suregaunkar 11,635 Reputation points Microsoft External Staff Moderator2026-04-09T11:06:55.66+00:00 Hello Lucas Harskamp
Thank you for posting your query on Microsoft Q&A platform.
We are looking into your issue and will keep you posted updates.
Thanks,
Suchitra.
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