This morning my wife brought me a problem. She was trying to read an email date 28-Apr, and the email came up blank. Then when she tried to open up some older mails, they still came up blank. Weird. So I went up and down the Inbox and determined that Anything between January 2009 and late April 2014 was basically coming up blank. I looked at the file size and it was 235MB. Small for 5 years. Much too small. That was on Windows. Copied the file to my Linux desktop and opened it up in Mutt. Mutt only counted 135 emails, some from 1 to 12 Jan 2009, one email date 7 July 2009 and the rest dated in May 2014. Nothing else. Returning to the Windows machine, I used the Thunderbird option to "Repair Folder" Inbox. The file size stayed the same and all deleted mail were removed from the index. At that point the Inbox on both Thunderbird and Mutt were identical. So basically, when she bought the problem to me, all those messages had already been removed from the Inbox, and the file had been compacted, but the index had NOT been rebuilt. Most, if not all, deleted messages were tagged as Junk, although I don't see why since very few probably were. There's also nothing in Trash and Trash is NOT configured to be emptied automatically on shutdown. Granted she is using an older version: 10; still the mbox format is supposed to be a solved problem. I don't expect Mozilla to fumble handling mbox. Could it have been file corruption? I don't buy that either, the file size would be larger and Mutt probably could not have read it cleanly. I am willing to assume that somehow she tagged 5 years worth of email as Junk; I will even assume that she might somehow have inadvertently deleted everything marked as Junk, even if that does not explain why some mail not marked Junk disappeared and some mail did not disappear even when marked as Junk. The only question is: why wasn't the index rebuilt? Philippe