In a Microsoft Exchange Server 2013 environment, messages are stuck in the Submission queue until nondelivery report (NDR) messages are returned or the server is restarted. Additionally, the following exception is logged in the message tracking logs:
This problem occurs because of handle leaks that cause the OleConversionServerBusyException exception in the transport.
Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.
Article ID: 3138644 - Last Review: Mar 15, 2016 - Revision: 1