Autodiscover 443 Office 365

Hi Guys,

While running Microsoft Remote Connectivity Analyser for my domain - for autodiscover I am getting below error on 443. It is working on port 80. Any help would be appreciate

Attempting to test potential Autodiscover URL
Testing of this potential Autodiscover URL failed.
Additional Details

Elapsed Time: 4135 ms.
Test Steps
Attempting to resolve the host name in DNS.
The host name resolved successfully.
Additional Details

IP addresses returned:,,,, 2603:1046:c01:892::8, 2603:1046:c01:840::8, 2603:1046:3:15::8, 2603:1046:1:16::8

Elapsed Time: 56 ms.

Testing TCP port 443 on host to ensure it’s listening and open.

The specified port is either blocked, not listening, or not producing the expected response.



Were you able to get this working properly @schouhan? The only thing odd I can see is a self-signed cert on the origin that may be causing an issue, but 443 is open.

The IP addresses listed in the test are Microsoft’s as is the testing tool. From my machine those resolve to 300 IN CNAME 210 IN CNAME 30 IN CNAME 34 IN A 34 IN A 34 IN A 34 IN A

Assuming the cname target of your record is correct (a question for Microsoft) the issue is Microsoft’s as well.

Unfortunately not. This isn’t working.

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Thanks :slight_smile: I get this. Sure I will get Microsoft attention to this also.

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Ticket # 17440921 was opened with Microsoft. However they responded -
This was there response -
" Using Activesync:
That’s only if they have mobile device use to connect to an Exchange server using active sync
Office 365 no longer needs that
However I will keep the update till this post doesn’t close down automatically.

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