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How to Fix Corrupt Eudora Mailboxes

Although Eudora 6.2.4 has taken some body blows from Mac OS X 10.5 Leopard, the email program largely keeps on ticking. That's not to say that it's as stable as it used to be, and I'm experiencing more crashes and oddities than in the past. Most recently, I was doing something with an in-progress message in the Out box and Eudora got confused, started chewing CPU time, and wouldn't respond to the keyboard or mouse. After a while I gave up and force quit the program by Option-clicking Eudora's Dock icon and choosing Force Quit.

Unfortunately, when I relaunched Eudora, all the messages in my Out mailbox since 14-Feb-08 showed a recovered status (a ?) instead of the correct status, and all of Eudora's automatically saved versions over the few days were visible. (When you use Eudora's auto-save functionality, it saves copies of your message as you type, but doesn't erase interim versions until you compact the mailbox, which happens automatically at various times and can be invoked manually by clicking the mailbox size box in the lower left corner of a mailbox window. To turn on auto-save on 2 minute intervals, click this x-eudora-setting:11520=120 URL within Eudora.)

But when I started checking out some of the interim versions of messages, it became clear that the problem went deeper, since message summaries for the recovered messages no longer matched their contents, and message contents no longer even filled in the appropriate fields in a message window. Clearly the mailbox's table of contents had become corrupted. In other programs, such a problem might require relying on a special database utility. But this is Eudora, which was developed when text files and resource forks ruled the Earth.

Long ago, Eudora creator Steve Dorner had told me how to fix a corrupted mailbox, and it's something that anyone can do by following these steps:

  1. Quit Eudora.
  2. Duplicate the Out box file, which is stored in ~/Documents/Eudora Folder/Mail Folder by default, so you have a backup copy. If you're nervous, make another copy on the Desktop. You can throw these out when you're done if everything goes well.
  3. Open the Out box file using a plain text editor like the free TextWrangler from Bare Bones. It may be a bit slow to work with a very large mailbox (mine was over 30 MB), but it should be able to handle the file.
  4. Copy the first line of the file, which should look something like the line below, and paste it on a line by itself at the very end of the file.
  5. From ???@??? Fri Jun 16 22:52:45 2006

  6. Save the file, being absolutely certain to save as plain text with Mac line breaks (likely the default in a plain text editor like TextWrangler).
  7. Launch Eudora again, and open the Out mailbox.

In theory, that should cause Eudora to realize that the table of contents, usually stored in the file's resource fork, is corrupt and to rebuild it by looking at the mailbox data itself. You may lose Eudora-specific data such as status and label, since that information exists only in the table of contents, but that's much less of a worry than not being able to access the messages at all. If it works for you, great, and you're done.

However, in my case, although this fix solved the problem of the messages not matching their message summaries, all the dates on the problematic messages were set to the same date. That wouldn't have been the end of the world, but I was unhappy about it, since I like to know when I sent a message. Referring to some more advice from Steve Dorner, I followed these steps (I used Tiger, and I expect they'd work in Leopard, but I'm less sure of Panther):

  1. Option-click the ? status for one of the messed-up messages to select all of them (insert obligatory "I can't believe other programs lack this insanely useful shortcut!" comment).
  2. Transfer the selected messages to a new temporary mailbox by choosing Transfer > New. Call the new mailbox tempBox.
  3. Quit Eudora.
  4. Now you need to delete the resource fork from the tempBox mailbox. Run Terminal and navigate to the folder containing the tempBox mailbox. (The easiest way to do this is to type "cd" and a space, drag the Mail Folder containing tempBox to the Terminal window, and then press Return.) Now enter this command:
  5. cp /dev/null tempBox/rsrc

  6. Launch Eudora again, open the tempBox mailbox to rebuild the table of contents, and verify that the dates have been fixed.
  7. Select all the messages and transfer them back to the Out box. Once they're back (Eudora may warn about losing headers or images that can't be found - don't worry about it), Option-click the unsent status (a hyphen) for the transferred messages to select all of them, click the status for one of them, and choose Sent from the pop-up menu to reset them all to the Sent status (a checkmark). (If you were performing this task on a mailbox other than Out, they'd all come in with an unread status (a bullet), and you could change that to read or replied or whatever). You can delete the empty tempBox mailbox.
  8. Lastly, go through and manually delete any interim versions of auto-saved messages. If you see four messages with the same Subject line, delete the first three, since the last one is the final version.

Some users have reported troubles with Eudora's tables of contents when running under Leopard, and they've worked around the problem by switching from Eudora's default method of storing the table of contents in the resource fork of each mailbox file to storing it in an old-style .toc file. You can toggle that setting in Eudora's Miscellaneous settings panel; there doesn't seem to be any harm in trying it, although Eudora will complain if you have any mailboxes with names longer than 27 characters, since the old-style .toc files date from the time when filenames couldn't be more than 31 characters. Just rename those mailboxes in the Finder when Eudora isn't running.

I tried this workaround but almost immediately ran into a problem where reading messages in certain mailboxes wouldn't update the status of those messages. It's possible I needed to delete the resource forks in those mailboxes manually, but unless I start having a lot more troubles, I'm going to stick with the normal resource fork approach to storing tables of contents.

For those of you who aren't happy with the workflow changes required by other email programs and are sticking with Eudora 6.2.4 as long as possible, I hope these instructions will keep your mailboxes healthy. But remember, there's no substitute for frequent backups, and if you're running Leopard, you should be backing up via at least Time Machine as well.


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Comments about How to Fix Corrupt Eudora Mailboxes

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Ian Cheong  2011-12-06 14:59
Still running Eudora 6.2.4 on early 2011 MBP downgraded to Snow Leopard. My Inbox got corrupted when eudora hung and I force quit it.

Following Adam's instructions (which usually work) resulted in a badly corrupted mailbox - headers looked fine but the mail text was not divided along the original message boundaries - text did not match headers at all.

Opening original corrupted mailbox in Textwrangler got a message "Incorrectly formed UTF-8 / The UTF-8 file is damaged or incorrectly formed; please proceed with caution."

This suggestion http://tinyurl.com/cga2kyj said to fix that to cut/paste the file. So that's all I did - open; select all; cut; paste; save and open in eudora. No other mailbox editing. Eudora still rebuilt the resource fork. My inbox is whole again (excluding read status of course) - 335MB!.

I always duplicate the corrupted mailbox file and save a compressed copy too (I use 7zX) - so I can retry any attempts to restore corruption. Will do more tests.
Ian Cheong  2012-04-21 21:18
Happened again. Forgot to read the directions. Copy/Paste didn't work. Cut/Paste did. 480MB this time. Just have to have enough free memory - ideally close everything except Textwrangler I guess. Still not game to end my relationship with Eudora!
jef chippewa  2012-02-04 10:42
found a super easy way to fix corrupted mailboxes, after reading here and another site .

i had message texts incorrectly separated AND identical dates on 2000+ messages (mailbox had 3500+ messages... yes, slimming it down now!).

close corrupted mailbox, quit Eudora, make compressed backup of "Eudora Forder", place copy of the corrupted mailbox on Desktop. open the mailbox with BBEdit, copy the first line (incl. line return), e.g. "From ???@??? Fri Jul 30 04:05:00 2010", and paste it at the very end of the file and save.

open Eudora, open the mailbox, the messages should flow correctly; identical dates will still be there.

close the corrupted mailbox, quit Eudora and return to BBEdit, delete the line pasted above. save.

open Eudora, open the mailbox, everything should be fine. i have some "Recovered" messages, they seem to be ones i have already transferred to appropriate mailboxes between encountering the corruption and fixing it.
Ian Cheong  2012-05-23 16:10
Great suggestion.

Silly me tried to transfer out the messages with intact headers prior to fixing the corruption. All that did was ruin a whole load of header dates. The Cut/Paste method didn't restore the dates on the newly corrupted messages.

The method by @jef_chippewa worked, leaving "?"=recovered in status of corrupted messages, contents intact.

Moral. Don't do anything to a corrupted mailbox until the corruption is fixed.
Mark Stolaroff  2013-02-19 21:21
Hey Jef, don't know if you'll see this, but I had the exact same problem, with just about the same number of emails in my Inbox.

Following your instructions, I was able to get Eurdora to separate correctly, but I can't fix the problem with all the dates being the same. I've run through the process several times, to no avail. Am I doing something wrong? Is there some little detail I'm overlooking?

Thanks for your help!
Paul Zelinsky  2014-03-13 10:43
I was so happy and relieved to find this page. Thank you all for the help!
Jim Kenzie  2017-06-21 17:37
Hello Jef: I know this post was ages ago, but my Eudora InBox just crashed and I'm hoping you might still be on the case and that your suggestion will work! Since John Myers passed on, we lost our Eudora guru. I am on Windows 7, so had to use a different editor (Thinkpad++). I tried to follow your instructions - copied the corrupted In Box into the editor, copied the first line into the last spot (wasn't sure if it got a carriage return, if that's a biggie, or even how I would check that...), saved it, and tried to open it with Eudora. But it didn't want to know! I think part of the problem might be the file type. I tried to save it as ".mbx"; didn't help. I changed it manually to ".mbx", still no joy! Either way when I launched Eudora my newly-created 'fake' In Box did not show up. I am the one-eyed man in the land of the blind; I have half a clue what I'm doing, but only half... Wondering where I went wrong? If you could help you would have a friend for life!!
Cheers, Jim
Unfortunately I haven't had success w these suggestions. Thankfully, for other than outbox, I've been able to do a recover by going to my partner's computer and copying the same inbox or folder that is hopefully still intact (he's on OS 10.4 and doesn't have as many Eudora crashes as I do on 10.5) onto a flash drive, then, with Eudora off, I drag the mail file into my Eudora MAIL or IMAP folder to replace my bad folders. When I restart E. all's fine. If I drag in a new folder that never existed in my own Eudora, it just adopts it like it was always there.

To replace or add just a few email instead of a whole folder, I drag the selected mail from my partner’s computer to my flashdrive, then open Eudora by clicking on the mail file on my flashsdrive, then drag the mail from the summary window into the folder I want it to be in.

Last, I only just discovered the Shift Key + Message>Change>Server..>Fetch Complete Message. Prior to using the Shift key, I’ve tried to Fetch no avail.
Adam Engst  An apple icon for a TidBITS Staffer 2013-01-27 10:34
If you're trying to recover IMAP mailboxes (as opposed to local POP mailboxes), that can introduce a whole new set of variables, and Eudora was never very good at IMAP, unfortunately.
Connie Smith  2013-11-26 22:23
OMG. Thank you thank you thank Jef! This worked. I can't believe it. I had totally screwed up my Eudora mailbox with over 15000 emails (I know!), and your method fixed it. I didn't think it was possible. THANK YOU!!!
Using Eudora 6.2 on OS 10.5 when the doc icon stopped working yesterday I deleted it. I then looked for Eudora.app in the applications folder but could not find it. I then attempted to reinstall Eudora but failed. I found the mbx file and clicked on it. It opened but only has mail since about 2008, which makes no sense because Eudora was working fine two days ago.
I don't know what to do.

Adam Engst  An apple icon for a TidBITS Staffer 2016-04-07 10:07
A Google search reveals that you can download a new copy of Eudora 6.2.4 from this page.


You'll need something that can decode BinHex (.hqx) files, like The Unarchiver.

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