Moving mail to “Local Folders” in Thunderbird

Recently, when moving mail from the uni’s mail server to Thunderbird’s “Local Folders”, a whole bunch of messages got corrupted. As you can see from the screenshot, the corrupted messages don’t have a subject, “from” is just a minus sign  and the date is always the same.


I tried everything suggested in Mozilla’s KB ( to restore the emails in question, but unfortunately to no avail. To make matters worse, we didn’t notice that the messages had been corrupted until about a month after it had happened and our mail servers only have a backup of the last ten days.


This is not an optimal solution, but will ensure that you don’t lose any mail when copying messages to your PC.

  • Select the messages you wish to move from the remote mail server to your local folders
  • Right click on one of the selected messages
  • Select “Copy To” / “Kopieren in”
  • Select “Local Folders” / “Lokale Ordner”
  • Select the folder to which you would like to move the mails. This will copy the mail to your PC,but not delete the original on the server.
  • Once the mails have been copied, check your local folders to make sure they are there and are previewing correctly
  • Delete the original mails from the mail server

I also made enquiries as to whether we were doing anything incorrectly, and if it would have been better to archive the mails instead. Judging by the answers that I received, it seems there is very little difference between Thunderbird’s (rather rudimentary) archiving system and its “Local Folders”.

For more robust archiving options in Thunderbird, see this article:

For more information on the size limits in Thunderbird, see this article:

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