This code occurs when conversion of an inbound SMTP failed because the code page that is specified in the message is not ...

{4}: This code occurs when conversion of an inbound SMTP failed because the code page that is specified in the message is not installed on the receiving server. This delivery status notification contains only the original message headers. None of the original content is provided. Troubleshooting: View the header of the original message. Make sure that the required language files are installed on the server that is receiving the message.