KB ID 0001652

Problem

While trying to connect Outlook (2016) to an Office 365 email account;

We can’t connect you

It looks like we can’t connect you to one of our services the moment. Please try again later, or contact your helpdesk if the issue persists.

0xCAA70010

{ADFS-URL}

Solution

This was happening because my ADFS server was using a ‘self-signed’ certificate (i.e. not a purchased one). This should NEVER be done in a production environment, but this is my test network, (so I refuse to spend money on certificates for testing etc!)

I cured the problem by simply importing/trusting the CA Certificate from my internal Certificate Services CA server, (that issued the ADFS servers certificate).

If you see this on a production server, with a publicly signed certificate, check that the ‘problem’ client does not need a Windows Update, to update its trusted CA Certificates, or that your certificate simply hasn’t expired, and you ‘forgot’ to renew it. If so;

ADFS: Changing the Certificate

Related Articles, References, Credits, or External Links

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