Here’s a quick post to describe an issue I didn’t see referenced anywhere else except for within forum replies.
Issue
A customer had Windows Server 2012 R2 Essentials configured with Office 365 Integration but noticed they were unable to make any changes to the integration (such as changing the Admin account or adding new users) and the Exchange Online-related status indicators in the Essentials Dashboard were not being displayed properly. The customer stated this issue happened once before but apparently resolved itself. However, in this case, functionality had been broken for several weeks before they decided to reach out to me.
Specifically, when running the O365 Integration wizard you would receive an error stating, “Cannot connect to Microsoft Online services…. Make sure that the computer is connected to the Internet and then try again.”
Resolution
I first looked under the C:\ProgramData\Microsoft\Windows Server\Logs folder within the SharedServiceHost-EmailProviderServiceConfig.log file for any Integration Tool errors.
The log revealed the following error messages:
BecWebServiceAdapter: Connect to BECWS failed due to known exception : System.ServiceModel.EndpointNotFoundException: There was no endpoint listening at https://bws902-relay.microsoftonline.com/ProvisioningWebservice.svc that could accept the message. This is often caused by an incorrect address or SOAP action. See InnerException, if present, for more details. —> System.Net.WebException: Unable to connect to the remote server —> System.Net.Sockets.SocketException: No connection could be made because the target machine actively refused
I was able to trace the error message to this Microsoft forum post where MVP Susan Bradley provided the resolution. In this case, the resolution was to navigate to the HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows Server\Productivity\O365Integration\Settings registry key and delete or rename the “BecEndPointAddress” registry entry. This entry had a value of the application server referenced in the error message above (bws902-relay.microsoftonline.com). After restarting all the Windows Server Essentials services, O365 Integration was fully restored.
My theory as to why this occurred is the application server the key referenced became inaccessible for some reason. I would think this value should be a load balanced name and not an individual server name.
Troubleshooting Exchange 