- Your mailbox is located on Microsoft Exchange Server 2013 or a later version of Exchange Server.
- Some messages that are sent to you through a custom send connector from another SMTP server (such as an Edge server) have the Smart Host Authentication Mechanism set to either BasicAuth or BasicAuthRequireTLS.
- These messages target a single server in the destination or a set of servers in a database availability group (DAG).
- Locate the MSExchangeFrontEndTransport.exe configuration file.
Note By default, this file can be found in the following location:%ExchangeInstallPath%Bin\MSExchangeFrontendTransport.exe.config
- Add the following line under <appSettings>:
// Add the following line.
<add key="ClientProxyPreferMailboxMountedServer" value="false" />
// End of the added line.
- Save the changes, and then restart the Front End Transport service on the server.
Article ID: 3195087 - Last Review: Oct 3, 2016 - Revision: 1