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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 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.
I think if you have your domain (www.mysite.com) hosted with one provider, and your email on O365 (and your DNS with another provider, perhaps), Outlook is trying to use your domain DNS record to validate your account (and not your MX record in DNS, which would point to O365).
Just a guess, but I get the same thing. I can't use 15.9 at all as every exchange account (O365 or otherwise) causes Outlook to crash. Yes I've tried the terminal commands - no dice.
Same issue here after installing 15.9.
Host name mismatch.
If I click continue, Outlook works for a while, but then it hangs and sometimes I have to force quit it.