Outlook SSL security warning after updating SSL on server

Question

I use ionus as a hosting company and I have SSL for all my domains. These update every year, and I just had the renewal. The SSL was updated on the cloud server properly, it seems to be installed in plesk properly, but outlook is not recognizing those updates. It seems outlook is stuck on the old/replaced SSL. How come outlook is not recognizing the updated SSL? I am getting a security warning for expired SSL every time, and i cannot send or receive messages, but the SSL has been installed properly on the server. Please help.

Answer 1

Hi @Thomas Kee ,

What's the type of your account? POP, IMAP or Exchange?
Does this issue only happen to this specific device? In order to further confirm if this is a client issue, if possible, it is suggested for you to try adding the same email account to Outlook clients on other devices and see if the issue has any difference.

As I know, usually if you got Security Certificate Warnings in Outlook, it means the security certificate your email server is using has expired or is invalid for other reasons. Have you tried viewing and updating your local certificate? If not, it is suggested for you to try the steps in this article: Security Certificate Warning in Microsoft Outlook and see if it could help resolve your issue. (Note: Since the web site is not hosted by Microsoft, the link may change without notice. Microsoft does not guarantee the accuracy of this information.)

By the way, if you are using POP/IMAP email account in Outlook, Outlook stores your server information in your account settings. So, please check your server port settings via Control Panel > Mail > E-mail Accounts > E-mail > Double click your email account > More Settings > Advanced. And make sure your Outlook settings could match your latest server settings.

Any updates, please feel free to post back.

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Answer 2

I have the same problem. we're self hosted, and i renewed the cert tuesday, then expanded the cert on wednesday to cover another domain as a Server Additional Name. Outlook keeps saying the cert was only updated tuesday. SSL labs shows the correct certificate
https://www.ssllabs.com/ssltest/analyze.html?d=mail.umfcorp.com&latest

the certificate serial numbers do not match.