Consulted a customer who reported the following error message when opening Apple Mail on her PowerMac G4:
“Mail cannot update your mailboxes because your home directory is full. You must free up space in your home folder before using Mail. Delete unneeded documents or move documents to another volume.”
A system check revealed that her start-up drive had plenty of free space available. A Google search uncovered an easy fix that’s documented on an Apple Support page.
1. Quit Mail if it’s running.
2. Choose Go to Folder from the Finder’s Go menu, then type :
3. Move the file named “Envelope Index” to the desktop (or the Trash).
4. Open Mail. Your will be alerted that your Mail messages will be imported again. Click OK.
5. Once the issue is resolved, you can delete the “Envelope Index” file from your desktop.
In my client’s case, I had to re-import her Mail messages twice to eliminate the error message. During the first pass, Mail reported that it needed to repair problems with some of the messages. The second pass reestablished normal access to Mail and caused the error message to disappear.