Help, please. My Tbird profile disappeared.

[tanstaafl]

"inbox.' is the mbox file that contains the messages for the inbox folder. "inbox.msf" is a so called index file, really just a cache of the folder listing that also stores some flags. "inbox.sbd" is a renamed directory used to help organize the mbox files into a folder hierarchy.

I try to use folder to refer only to a mail folder in Thunderbird, not a directory on the hard disk. Otherwise it gets confusing.

Sorry, but it sounds like you are out of luck recovering messages from the two corrupt inbox mbox files unless you manage to spot something wrong when looking at the raw source code in a text editor. I tried to describe how to do it in the "Edit mbox file - Advanced" section of the KB article but most users won't be comfortable attempting to do that because they aren't familiar enough with the Multipurpose Internet Mail Extensions (MIME) standard.

Thunderbird defaults to using the mbox format. However, it now also supports the maildir format, which stores each message as a .eml file (with no file extension). The code for that format is not as mature, so its riskier when moving messages between mbox and maildir based accounts, but it seems to work pretty well overall. Think about switching formats to avoid similar problems in the future. You will no longer need to deal with compacting and you don't need to risk losing an entire folder just because one message got corrupted.

The release notes for version 60 state "Thunderbird now allows the conversion of folders from mbox to maildir format and vice versa. This is an experimental feature that needs to be enabled by setting the preference mail.store_conversion_enabled. Note that this functionality does not not work if the option "Allow Windows Search/Spotlight to search messages" is selected." I've done that several times, with no problems.

https://wiki.mozilla.org/Thunderbird/Maildir is out of date but might be useful

[Mark246]

Thanks very much for all of your help, tanstaafl.
I've finished restoring the 2-month-old backup, and also copied a few of the emails from the Recuva files.
That's about as good as it's gonna' get.
I Seriously appreciate your time and expertise. Many Thanks.
Mark246