Robert,

You will have to modify the files slightly that are sitting in the OutboundMailQueue. Here are the steps:

• Open $INSTALL_DIR\OutboundMailQueue folder
• Open any file sitting there in Notepad
• Search for X-SMCustomAuth .
• The goal is to remove this header from the email that are sitting in your OutboundQueue. The quickest way is to use a utility that can do search/replace inside files and replace X-SMCustomAuth with some garbage value. For example X-SMCustomXXXAuth

The actual problem is occurring when Xeams is trying to use the Smart Host even for incoming messages.