Are you trying to connect internally or from the Internet?
Internally, configure the URL using Set-ClientAccessServer -AutodiscoverServiceInternalUri. Externally, autodiscover.company.com (where company.com is your e-mail domain) must reach the Exchange server, as well as the hostname you use for Outlook
Anywhere, e.g., webmail.company.com. For either, you need a valid SSL certificate with both names that is trusted by the client.
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