Hi everyone, I've been having an odd issue with a recently migrated Exchange 2010/Windows 2008 R2 server. When our users go to settings from OWA, and click most settings they get an error which states "An item with the same key has already been added". I've Googled around and can't really find anything useful... An exact example of how to replicate the error is: Login to OWA, click 'options' in top right corner. then click settings on left side and the error appears as a small web generated box titled 'Error' with the message "An item with the same key has already been added". Most of the pages within settings produces the error. I have also found that the Outlook client cannot set OOA - it reports that the server is unreachable.. we've created an autodiscover A record in DNS to point to the correct URL. I'm wondering if we need an SSL cert for the A record? It throws up the standard 'untrusted server' message, but allows us to tell it to continue anyway. I've also got some test results from the Test-OutlookWebServices cmdlet. It also points at the autodiscover service. RunspaceId : df0faa81-7b95-4f99-b17c-21b01a811d38 Id : 1019 Type : Information Message : A valid Autodiscover service connection point was found. The Autodiscover URL on this object is https://we bmail.myexternaldomain.com/autodiscover/autodiscover.xml. RunspaceId : df0faa81-7b95-4f99-b17c-21b01a811d38 Id : 1013 Type : Error Message : When contacting https://webmail.myexternaldomain.com/autodiscover/autodiscover.xml received the error The rem ote server returned an error: (500) Internal Server Error. RunspaceId : df0faa81-7b95-4f99-b17c-21b01a811d38 Id : 1023 Type : Error Message : The Autodiscover service couldn't be contacted. RunspaceId : df0faa81-7b95-4f99-b17c-21b01a811d38 Id : 1113 Type : Error Message : When contacting https://DC02.myinternaldomain.local:443/autodiscover/autodiscover.xml received the error The underlyin g connection was closed: An unexpected error occurred on a send. RunspaceId : df0faa81-7b95-4f99-b17c-21b01a811d38 Id : 1113 Type : Error Message : When contacting https://DC02.myinternaldomain.local:443/autodiscover/autodiscover.xml received the error Unable to rea d data from the transport connection: An existing connection was forcibly closed by the remote host. RunspaceId : df0faa81-7b95-4f99-b17c-21b01a811d38 Id : 1113 Type : Error Message : When contacting https://DC02.myinternaldomain.local:443/autodiscover/autodiscover.xml received the error An existing c onnection was forcibly closed by the remote host RunspaceId : df0faa81-7b95-4f99-b17c-21b01a811d38 Id : 1123 Type : Error Message : The Autodiscover service couldn't be contacted. RunspaceId : df0faa81-7b95-4f99-b17c-21b01a811d38 Id : 1013 Type : Error Message : When contacting https://dc02/EWS/Exchange.asmx received the error The underlying connection was closed: An unexpected error occurred on a send. RunspaceId : df0faa81-7b95-4f99-b17c-21b01a811d38 Id : 1013 Type : Error Message : When contacting https://dc02/EWS/Exchange.asmx received the error Unable to read data from the transport c onnection: An existing connection was forcibly closed by the remote host. RunspaceId : df0faa81-7b95-4f99-b17c-21b01a811d38 Id : 1013 Type : Error Message : When contacting https://dc02/EWS/Exchange.asmx received the error An existing connection was forcibly clos ed by the remote host RunspaceId : df0faa81-7b95-4f99-b17c-21b01a811d38 Id : 1025 Type : Error Message : [EXCH] Error contacting the AS service at https://dc02/EWS/Exchange.asmx. Elapsed time was 0 milliseconds. RunspaceId : df0faa81-7b95-4f99-b17c-21b01a811d38 Id : 1013 Type : Error Message : When contacting https://dc02/EWS/Exchange.asmx received the error The underlying connection was closed: An unexpected error occurred on a send. RunspaceId : df0faa81-7b95-4f99-b17c-21b01a811d38 Id : 1013 Type : Error Message : When contacting https://dc02/EWS/Exchange.asmx received the error Unable to read data from the transport c onnection: An existing connection was forcibly closed by the remote host. RunspaceId : df0faa81-7b95-4f99-b17c-21b01a811d38 Id : 1013 Type : Error Message : When contacting https://dc02/EWS/Exchange.asmx received the error An existing connection was forcibly clos ed by the remote host RunspaceId : df0faa81-7b95-4f99-b17c-21b01a811d38 Id : 1027 Type : Error Message : [EXCH] Error contacting the UM service at https://dc02/EWS/Exchange.asmx. Elapsed time was 0 milliseconds. Oh, and finally the internal domain address doesn't have an SSL certificate assigned to it - do you think this could be causing issues? Any ideas?