I'm using EWS for a C# client that subscribes to new mail notification. We currently have what I believe are 4 client access servers in our environment. If I use autodiscover to find the correct CAS I often get what appears to be the wrong one. I know when it picks the wrong one because if I send myself an email (which should trigger a new mail notification) my client is never notified. I am able to get notifications working for a while (time is undetermined) if I hard code which CAS (this is a guessing game on my part) I wish to connect to, however that stops working when the mailbox moves client access servers. I'm using
InternalEwsUrl. This is a fully patched Exchange 2010 SP1 server.
Looking at the stack trace I see that it correctly finds all 4 client access servers with a priority of 1. It always picks the top most CAS (assuming this is default behavior), which is more often than not incorrect.
Any idea as to why I'm not always resolving the proper CAS?
Note: I'm a developer and not a system administrator so if I said something that doesn't make sense or requires clarification, please tell.