Corruption in mailbox

[Steevo]

I've been using eudora for a very long time.

I have a corrupt mailbox. All this mailbox was filtered from inbox on receipt.
The inbox seems to have no problem.
My first clue is error messages if I try to view a message newer than a couple of weeks. Messages before that are OK.
I do notice that the size in the lower left info panel instead of beginning with a _number instead has a _-number. When corrupt.
I was able to copy all the messages before the corruption occurred to a new mbx and that works fine, but I have a couple of weeks of missing mail. I'm afraid to filter new mail to it, I did that and it became corrupt. I suspect a bad message on the server that caused all this.

When I open the corrupt mbx file I get a popup that the file is not found, then the toc is rebuilt and the file opens. But I can only see messages that are a month or more old, later than that, they are corrupt and open blank.

When I try to open a message that is new,
I get a message that the request contains an invalid argument,
then one that says error in reading the mailbox,
and then unable to write to temporary file.
Then the message opens blank.

Turning off microsoft's viewer loads messages as text. No problems. But messages that I have previously opened are still blank. Odd.

Is there any software tool that can read and write the messages from a mbx file that seems corrupt, and fix the problems, hopefully free?
Someone had some stuff in an archive somewhere.
Heck, 5 or 6 computers ago I probably had that stuff.

[Dennis Lee Bieber]

Post by Steevo
I was able to copy all the messages before the corruption occurred to a new mbx and that works fine, but I have a couple of weeks of missing mail. I'm afraid to filter new mail to it, I did that and it became corrupt. I suspect a bad message on the server that caused all this.
When I open the corrupt mbx file I get a popup that the file is not found, then the toc is rebuilt and the file opens. But I can only see messages that are a month or more old, later than that, they are corrupt and open blank.

How large is this mailbox?

Eudora is a 32-bit application, and as such can only manage file sizes
that can be addressed with a 32-bit offset (technically, if treated as
UNSIGNED, that would be 4GB -- but most programs use a SIGNED integer, so
the offset maximum is 2GB).

Post by Steevo
Is there any software tool that can read and write the messages from a mbx file that seems corrupt, and fix the problems, hopefully free?

MBX files are a variant of standard UNIX MBOX... Plain text file!
Messages with a line reading

FROM ***@somewhere

{though Eudora just saves ???@??? format} and end with a blank line... and
any line in the body that happens to begin with the word FROM is edited to
begin with >FROM {Not sure if case matters}

Eudora uses the TOC file to identify which messages have been read or
are still unread. The TOC file may also have an offset to each message in
the MBOX.

Any software that can read a UNIX MBOX file should be able to read the
MBX files... But writing a new file won't produce a valid TOC file for
Eudora.

Note that if you have deleted messages, but have NOT compacted the
mailbox, the text of those deleted messages will still be in the file --
the deletion status is part of the TOC file. Utilities that don't know TOC
will see all messages in the MBX file.