Once mastered, open Mail and open the Mailbox option in the menubar.
Choose Rebuild and let it do its thing.
On completion, close Mail and reopen it.
Did the problem go away?
On the subject of a virus. There are no viruses that are effective against OS X, but it is possible that there is a Windows virus attached to one of those emails.
However, even if there was, it would not do anything against your Mac.
P
TODAY I STARTED WITH 17 JUNK EMAIL MESSAGES (THE USUAL ADVERTISEMENTS, ETC.) EVERY TIME I TRY TO DELETE THEM FROM TRASH I GET STRANGE MESSAGE I HAVE NEVER SEEN BEFORE, AND NUMBER OF EMAIL MULTIPLIES. THE MESSAGE SAYS THIS- "THE COMPACTED MAILBOX IS NOT THE EXPECTED SIZE, PERHAPS BECAUSE THE DISC IS FULL. THE MAILBOX WILL BE RESTORED TO ITS STATE BEFORE COMPACTION." (THIS CAN NOT BE TRUE THAT MY EMAIL BOX IS FULL BECAUSE I ONLY HAD ABOUT 15 IN INBOX, AND MAYBE 50 IN SENT BOX.) I HAVE TRIED DELETING THE PROBLEM (SPAM) MESSAGES DIRECTLY FROM CHARTER.COM, WHICH I DID, BUT THIS DOES NOT AFFECT THE ACTUAL EMAIL PROGRAM. I AM UP TO OVER 500 MESSAGES AND THE EMAIL PROGRAM IS ABOUT USELESS, ANY HELP OR SIMILAR PROBLEMS REPORTED (THE MULTIPLYING MESSAGES UPON DELETION THING?) I HAVE NEVER HEARD OF THIS. IS IT POSSIBLE ONE OF THE MESSAGES CONTAINED VIRUS? WHAT CAN I DO TO RESTORE MY EMAIL PROGRAM?

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