EDIT 9/19/2023: This blog post has received significant update.
In this second part of the Demystifying Hybrid Free/Busy, we will cover troubleshooting of Hybrid Free/Busy scenarios, more specifica...
Updated Sep 19, 2023
Version 16.0
Blog Post
I have ONE user whose mailbox is in Office 365 EXO who cannot see any free/busy information on my Exchange 2016 on premise environment. I have engaged Microsoft Support but it's not going anywhere. This is the error it gives:
Performing Free/Busy Lookup
Free/Busy Lookup failed.
Additional Details
Free/Busy Lookup failed with exception: Autodiscover failed for email address email address removed for privacy reasons with error System.Net.WebException: Unable to connect to the remote server ---> System.Net.Sockets.SocketException: A connection attempt failed because the connected party did not properly respond after a period of time, or established connection failed because connected host has failed to respond 4.1.70.82:443 at System.Net.Sockets.Socket.InternalEndConnect(IAsyncResult asyncResult) at System.Net.Sockets.Socket.EndConnect(IAsyncResult asyncResult) at System.Net.ServicePoint.ConnectSocketInternal(Boolean connectFailure, Socket s4, Socket s6, Socket& socket, IPAddress& address, ConnectSocketState state, IAsyncResult asyncResult, Exception& exception) --- End of inner exception stack trace --- at System.Web.Services.Protocols.WebClientAsyncResult.WaitForResponse() at System.Web.Services.Protocols.WebClientProtocol.EndSend(IAsyncResult asyncResult, Object& internalAsyncState, Stream& responseStream) at System.Web.Services.Protocols.SoapHttpClientProtocol.EndInvoke(IAsyncResult asyncResult) at Microsoft.Exchange.SoapWebClient.AutoDiscover.DefaultBinding_Autodiscover.EndGetUserSettings(IAsyncResult asyncResult) at Microsoft.Exchange.InfoWorker.Common.Availability.SoapAutoDiscoverRequest.<>c__DisplayClass48_0.<EndInvoke>b__0() at Microsoft.Exchange.InfoWorker.Common.Availability.SoapAutoDiscoverRequest.ExecuteAndHandleException(ExecuteAndHandleExceptionDelegate operation)., inner exception: System.Net.WebException: Unable to connect to the remote server ---> System.Net.Sockets.SocketException: A connection attempt failed because the connected party did not properly respond after a period of time, or established connection failed because connected host has failed to respond *.*.*.*:443 at System.Net.Sockets.Socket.InternalEndConnect(IAsyncResult asyncResult) at System.Net.Sockets.Socket.EndConnect(IAsyncResult asyncResult) at System.Net.ServicePoint.ConnectSocketInternal(Boolean connectFailure, Socket s4, Socket s6, Socket& socket, IPAddress& address, ConnectSocketState state, IAsyncResult asyncResult, Exception& exception) --- End of inner exception stack trace --- at System.Web.Services.Protocols.WebClientAsyncResult.WaitForResponse() at System.Web.Services.Protocols.WebClientProtocol.EndSend(IAsyncResult asyncResult, Object& internalAsyncState, Stream& responseStream) at System.Web.Services.Protocols.SoapHttpClientProtocol.EndInvoke(IAsyncResult asyncResult) at Microsoft.Exchange.SoapWebClient.AutoDiscover.DefaultBinding_Autodiscover.EndGetUserSettings(IAsyncResult asyncResult) at Microsoft.Exchange.InfoWorker.Common.Availability.SoapAutoDiscoverRequest.<>c__DisplayClass48_0.<EndInvoke>b__0() at Microsoft.Exchange.InfoWorker.Common.Availability.SoapAutoDiscoverRequest.ExecuteAndHandleException(ExecuteAndHandleExceptionDelegate operation)
When I use a different user account of someone whose mailbox is also in EXO and run the exact same test without any changes, it completes with this information:
Performing Free/Busy Lookup
Free/Busy Lookup completed successfully.
Additional Details
Results for ******@****.org which consists of appointments that include today's date Free 8/15/2023 4:00:00 AM - 8/16/2023 4:00:00 AM UTC Busy 8/16/2023 1:15:00 PM - 8/16/2023 2:45:00 PM UTC Busy 8/16/2023 6:00:00 PM - 8/16/2023 6:30:00 PM UTC
Performing Server Time check
Server Time check completed successfully.
Additional Details
Server Time check completed successfully. HTTP Response Headers: request-id: 27f11c9f-7587-4abb-8b1e-48de0d02aa4f X-WSSecurity-Enabled: True X-WSSecurity-For: None X-OAuth-Enabled: True X-OWA-Version: 15.1.2507.31 Content-Length: 0 Server: Microsoft-IIS/10.0 WWW-Authenticate: Negotiate WWW-Authenticate: NTLM X-Powered-By: ASP.NET X-FEServer: **** Date: Wed, 16 Aug 2023 19:01:17 GMT
Again, I am performing the test the same exact way and both users are the same, but one works and one fails. I have compared AD attributes, made sure that the exo exchangeguid matches on both sides, I am just lost. Any help would be appreciated.