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I just installed Outlook v15.9 as well as updates for the entire new Mac 2016 suite released yesterday. I'm getting an Outlook certificate error as can be seen in the attached screen shot. I can click Continue and run Outlook without any problems and it works fine. Also, I wasn't getting this error in the immediate prior release. All of my company's email is hosted on Office 365. How can I fix this or should I worry about it? Thx! John
Using older versions of Outlook for Mac in business environments
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I'm seeing the same thing. Does no one from the Mac Preview team monitor these forums? Five days and no response or acknowledgement of the issue?
I agree that this isn't an OS X 10.10.3 issue or an hosted Exchange issue.
I am getting the same type of popups with our on premises Exchange 2010 server and with an Exchange 2013 server.
This is a bug in the Outlook 2016 15.9 update in the way Outlook is trying to get the certificate information.
It appears that when Outlook 2016 is validating the certificate, it uses the root domain instead of the actual server name used for connectivity.
For example, if your ActiveSync or Outlook Anywhere server is webmail.mydomain.com, 15.9 will try to use mydomain.com. Prior to 15.9, it would use webmail.mydomain.com.
Besides, the constant crashing, I'm going to uninstall Outlook 2016, 15.9 and reinstall a prior version.
Just my two cents,
Paul K
I had 10.10.3 and Outlook working fine, up until 15.9 came out. Worked fine for almost a week without one of these certificate errors coming up until 15.9 was installed. I have my domain hosted elsewhere too. Seems to be the common link.
I don't think this is the culprit. I have selected this but it does not resolve the issue. What is odd is my cert pop up is for the provider hosting my web site, not the cert for Microsoft (O365).
I did that. I do not believe that is the problem.