The sign-in to Outlook Web App failed. User %1 has a mailbox on %2 server version. However, no Client Access server or front-end ...

The sign-in to Outlook Web App failed. User %1 has a mailbox on %2 server version. However, no Client Access server or front-end server with a matching version was found to handle the request.



For users on Exchange 2007 and above, you can configure the Outlook Web Access URL for redirection using the externalURL parameter on the Exchange /owa virtual directory.