Summary. The Apple Mail client database files can become corrupted and incorrectly indicate that one or more unread messages are present in the inbox or other folders. This document explains how to fix the problem.
Problem Solution. These instructions are written for Apple Mail Version 5.2 included with Lion, but the general approach should work with older versions. This process may take a while if you have many saved emails.
- With no programs running, from your desktop, press the option (alt) key and click on the Go menu to find Library. It won’t show up if you aren’t holding down the option (alt) key. Click on Library.
- Navigate to Library > Mail > V2 > MailData.
(This means to find the Mail folder in Library, then find the V2 folder, and in the V2 folder find the MailData folder) - Within the MailData folder, you’ll find some files that begin with Envelope. Drag those to your desktop.
- Start the Mail program. This will cause the program to completely reindex and rebuild all of your mailbox information, and it should resolve the problem
Mail Message Import. Below is a graphic showing the window that will appear when you start Mail for the first time after deleting the Envelope files.
Message Import. Once the importing process begins, you’ll see a window similar to the one below providing a progress indicator and estimated time remaining.