Mailboxes were unable to connect after Exchange 2013 CU8 install

Scenario:  After upgrading our Exchange environment to CU8, users were reporting that they were unable to connect to their mailbox.  After investigation, it was narrowed down that only a few servers were showing this issue, and other recently updated servers were working fine.


  • Outlook Anywhere was showing as disconnected.
  • OWA was taking mailboxes to a blank white page.
  • Mobile Devices were reporting that there were issues connecting to the server
  • Failure to connect to the Exchange Management Shell
  • Multiple events in the System Log of the affected servers: Event ID 15021 (Source: HttpEvent): An error occurred while using SSL configuration for endpoint  The error status code is contained within the returned data.

Cause/Resolution: The problem was found to be that the Exchange Back End virtual directory in IIS was no longer bound to a SSL certificate; thus users were not able to establish a connection to their mailboxes.

  1.  Open IIS Manager
  2.  Expand the Server Name –> Sites.
  3.  Right click on the  Exchange Back End site.
  4.  Click on Edit Bindings.
  5.  Edit the entry for https port 444.
  6.  Select a valid SSL vertificate from the list. A certificate needs to be set and this was set  to none and was causing the issue.



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