TLS errors when connecting to mailbox

Graham Jenkins 6 Reputation points


Apologies if this is in the wrong location.

We have an app registered in Azure which allows our software to "import" emails from mailboxes into our software using OAuth; as well as send emails via our software. Since yesterday, we have noticed that emails are getting duplicated in our system as well as connectivity errors for outbound emails. Our development team believe that our attempt to mark the email as "Read" is failing so we import it again during the next scan.

In Windows Event viewer, the below error is occurring;


One of our customers ran msmd.exe and the only error in there is "An internal server error occurred. The operation failed". Have also tried but no success. No changes/updates made to our software. Affecting multiple end users across multiple sites. Mailboxes using Basic Authentication are unaffected. Have there been any changes to permissions or changes TLS made?

Microsoft Entra ID
Microsoft Entra ID
A Microsoft Entra identity service that provides identity management and access control capabilities. Replaces Azure Active Directory.
19,362 questions
0 comments No comments
{count} votes

2 answers

Sort by: Most helpful
  1. Andy David - MVP 140.8K Reputation points MVP
    2 people found this answer helpful.

  2. JimmySalian-2011 41,916 Reputation points


    By default TLS1.2 is enabled on the clients and servers , however if someone has disabled it for a reason you can check and enable it enable-support-tls-environment

    Also you will need to check .NET version, Update and configure .NET Framework to support TLS 1.2

    Please "Accept the answer" if the information helped you. This will help us and others in the community as well.

    0 comments No comments