First the work around to this issue that does work then Microsoft’s fix , the Client Access Service kept restarting on Exchange 2013, this did not really effect the server side of things however users kept getting a message in Outlook that they had been disconnected. The first thing I did was to set the service to restart on fail. This resolved this issue but after 3 restarts the services still caused and issue with Outlook clients. You will see the error message below.Event code: 3005
Event ID: cf8a97b6012e407fabfe5c3386ae886f
Event sequence: 69
Event occurrence: 68
Event detail code: 0
Application information:
Application domain: /LM/W3SVC/1/ROOT/Rpc-1-129972611679238809
Trust level: Full
Application Virtual Path: /Rpc
Application Path: C:\Program Files\Microsoft\Exchange Server\V15\FrontEnd\HttpProxy\rpc\
Machine name: MAIL
Process information:
Process ID: 35200
Process name: w3wp.exe
Account name: NT AUTHORITY\SYSTEM
Exception information:
Exception type: HttpException
Exception message: The client disconnected.
at Microsoft.Exchange.HttpProxy.ProxyRequestHandler.EndProcessRequest(IAsyncResult result)
at System.Web.HttpApplication.CallHandlerExecutionStep.OnAsyncHandlerCompletion(IAsyncResult ar)
Request information:
Request URL: https:// mail.xxx.co.uk:443/rpc/rpcproxy.dll?f00b901e-3901-4bdc-b531-1d036a08a5ce@cloud4mobile.nl:6001
Request path: /rpc/rpcproxy.dll
User host address: fe80::d840:8673:71f4:c865MAIL
User: XXX\SM_ca58c7458c9b4b759
Is authenticated: True
Authentication Type: NTLM
Thread account name: NT AUTHORITY\SYSTEM
Thread information:
Thread ID: 58
Thread account name: NT AUTHORITY\SYSTEM
Is impersonating: False
Stack trace: at Microsoft.Exchange.HttpProxy.ProxyRequestHandler.EndProcessRequest(IAsyncResult result)
at System.Web.HttpApplication.CallHandlerExecutionStep.OnAsyncHandlerCompletion(IAsyncResult ar)
I evetually created a long term work around by adding a registry key that extends the timeout with the following key
HKEY_LOCAL_MACHINE/Software/Policies/Microsoft/Windows NT/
Then create the DWORD key
MinimumConnectionTimeout
With a VALUE of 120
After implementing the fix I had time to dig further, it turns out that this is an issue with ASP.net check out the Microsoft support link here.