System Administrator message

Question

Several times in the last few weeks I have suddenly received an email headed System Administrator message unavailable. It says: "This message is no longer available on the server."  On one occasion I was online with my ISP support when this message came in direct to my email client, and then as we watched, five minutes later it appeared on the ISP server. I am concerned about what or who originated the message, as it did not come from the ISP. Could it indicate a hacker has got access to my system? Can anyone suggest?

Answer 1

This is what I get when I contact support. 
These aren't true emails, because they are missing all the common requirements of an email such as 'Received' and 'Date' headers. This message was not generated by the SMTP application that receives all email from the internet and puts it in the mailbox.  Something else placed it there.  More over, the mail server is smart enough that it wouldn't refer to itself as 'localhost', only a poorly configured server wouldn't put their true name in. Here's a clue:
  http://markmail.org/message/44ginmx6wytjalbx
So it would appear the mail server is running the same patch this person proposes in this email.  Whenever your email client requests a messageID that doesn't exist (anymore), it returns this string and apparently creates an item in your inbox. The timestamps on the files above seem to coincide with an IMAP login:
Jan 22 17:46:52 atlas2 imapd: LOGIN, user=[email protected], ip=[::ffff:24.234.221.37], port=[50921], protocol=IMAP Perhaps because the headers are missing, the email client might repeated request the messages without recognizing them as being something it has seen before and present them as new emails. I removed the four emails from the inbox.  Lets see if they come back.  If they do, I might ask you to 'reindex' or 'repair' the inbox mailfolder in the email client.
He states I should reindex or repair the inbox folder.  I'm not sure how to do that for mac2011 outlook.