Hosted Exchange Autodiscover/ActiveSync services do not work:
Autodiscover URL (https://autodiscover.provider.com/Autodiscover/Autodiscover.xml) gives error message:
500 System.Net.WebException: The operation has timed out at System.Net.HttpWebRequest.GetResponse() at AutodiscoverProxyHandler.Handler.ProcessRequest(HttpContext context)
Event Viewer on Exchange CAS servers shows error like this:
Wrong binding [::1]:80: is configured on the default website in IIS on CAS servers. It was probably added by some Exchange update.
Remove wrong binding [::1]:80: from the default website in IIS on CAS servers.