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Hi
The pictures below started popping up on our PCs. and the PC was using not part of any domain. I tried to follow the link below but the IE was inaccessible. https://answers.microsoft.com/en-us/outlook_com/forum/all/outlookoffice365com-security-certificate-has-been/743bdb2b-06ce-4206-923e-bdb7041528bd
Using classic Outlook for Windows in business environments
I am not a computer person and also have this problem. I clicked into the Security Alert message's "View Certificate" button and saw that the certificate is issued to "outlook.com" while the security message said the internet address "outlook.office365.com" has security concern. That to me essentially is a Microsoft mess up by using Peter's credential to do business as Paul.
I think that I started to have this pop up issue around when the new certificate became effective, that was 7/25/2022.
As to some PCs/Macs don't have the issue maybe because they already have the correct security certificate installed on their computers. There is no setting in my hotmail setup for me to change in Outlook, so so far I am dealing with it by clicking ok on the box everyday.
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I just want to also chime in that we're getting more calls from our users about this same issue. Outlook clients and iOS Mail users are getting prompted with the security pop-up.
I've just opened a ticket with Microsoft yesterday about this issue. They've just asked some initial discovery questions and haven't gotten back to me yet.
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Same thing here. Only about 10 percent of the users are seeing this error. Approx 60 users. This has been going for about 6 months.
All are AD systems.
AZURE AD sync is active and syncing properly
Mix of Windows 10 and Windows 11 devices. All users have Office 2019.
Currently only getting reports from users on Windows 10 but that could be a coincidence.
Anyone getting this on Windows 11?
I usually tell the user to reboot and report back if it happens again. I never hear back. It's pretty random. I think it happens if the user has a brief connection issue such as a couple dropped packets. Hoping it's something easy to fix such as upgrading from Windows 10 to Windows 11.
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Hi
Today we got a lot of those certificate Revoked popup.
Even on iPhones.
Usually i get 1 or 2 popup monthly.
Domain environnement
Azure AD and synching.
Mix of Win10 and 11
Office 2019 32 bit
The only thing im realizing for now is this seems to only happen when staff is on site....
Date and time is perfect.
Still investigating...
Sorry for my english :-/
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I can confirm that this is happening on both AD systems and non-AD systems. I've had it happen to me on both types of systems. I'm on a non-AD tenant that it happened to me on yesterday and on an AD tenant that it happened to me on this morning.
Also, happening to me whether I'm on a VPN or not on a VPN. The only software that's talking to outlook.office365.com on either machine is Outlook. I'm not using OWA on either machine.
Anyone here using appliance with content filtering or else ? Watchguard, Fortinet or else ?
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What MS Office desktop app do you use? The below link is for version 2013 and I hope this will help to resolve your issue.
Topic: Outlook 2013 displays a prompt that lets you connect to an Exchange server if a certificate issue occurs (microsoft.com)
Thanks,
Edgar
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Apple Mail app on
Mac also gets this warning.
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I also have recently started encountering this error message. I use Microsoft 365 through Outlook on my Windows computer, with the latest versions of Windows 10 and Office 365. The Exchange server is hosted by Microsoft.
If I click "OK" when the message pops up I can continue as before.
It would be good to understand what is causing this error message...
