Problem definition

Emails with MIME header that do not comply to the RFC2046 convention will be rejected by the Service Desk incoming mail handler.

• There was an error reading the body of email message. will be seen in the Processing log for the rejected email.
• Error below appears in the atlassian-jira.log

  2017-08-28 09:17:06,643 Caesium-1-3 WARN admin@atlassian.com     [c.a.s.i.feature.emailchannel.IncomingEmailParser] Error processing email message
  java.io.IOException: Unknown encoding: 7-bit
  	at javax.mail.internet.MimePartDataSource.getInputStream(MimePartDataSource.java:115)
  	at com.sun.mail.handlers.text_plain.getContent(text_plain.java:80)
  	at javax.activation.DataSourceDataContentHandler.getContent(DataHandler.java:795)
  	at javax.activation.DataHandler.getContent(DataHandler.java:542)
  	at javax.mail.internet.MimeBodyPart.getContent(MimeBodyPart.java:657)
  ...
  

Suggestion

Better approach to handle emails with invalid header

Notes

The cause of the issue is that the mail server is sending emails with an invalid encoding which cannot be processed by javamail. The workaround is to change the mail server settings to send base64 or binary encoded emails to the Service Desk email channel.