Fixing Mail import crashes on Leopard

After restoring from a Time Machine backup, Apple Mail would crash every time I tried to re-import my email archive. The problem seems to be affecting a lot of people who have mail that pre-dates OS X. The same crash also happens after migrating to a new machine.

Quick fix

Copy the following command and paste it into your Terminal. Press return and wait a few minutes. Once the command finishes, Mail should be able to import your messages.

grep -lZr 'Content-disposition: attachment' ~/Library/Mail/Mailboxes/ | xargs -0 ruby -i -pe 'gsub(/(Content-type:[^;]*;\s*name=)"(.*)"/){$1+(if !$2.nil? then $2.dump.gsub(/\\\\/, "\\") end)}'

The problem

The problem is specific to older, MacRoman encoded email messages with attachments whose filename includes non-ascii characters. For whatever reason, that freakshow edge-case combination will crash Apple Mail every time it tries to import those files. If by some stroke of luck you already have these messages in your email archive (I did), they can still crash Mail when trying to rebuild the containing mailbox.

The solution is sort of simple, just rename the attachment in the .emlx file. The harder part is finding which file to edit.

We’ll use grep to recursively search for a common token in these older files, then pass the filenames to a Ruby snippet which will filter the line containing the bad characters. Here is a section of a suspect message’s header:

Content-type: application/octet-stream; name="SPWH 4.01ü.sit";
Content-disposition: attachment
Content-transfer-encoding: base64

The first bolded line contains the attachment name which is causing the problem, who knows what that umlaut was originally. The second bolded line is what we’re telling grep to locate, I couldn’t get anything to dependably match the oddball characters. “Content-disposition” appears to be an older attachment syntax and didn’t appear in any of my messages from after 2001.

While the Ruby script could be run from find’s exec command, it wouldn’t be particularly efficient. Calling the script from find would pass every .emlx file in the Mailboxes directory through Ruby’s gsub, which is almost wholly unnecessary (and much slower). Only 10 of my 57,007 messages needed fixing, 99.98% of them were fine.

Is this safe?

Since the most common way to encounter this bug involves Time Machine restores or migration to a new machine, most users should already be backed up. If something should go wrong, just restore the backup’s Library/Mail folder over the messed up one. You can also copy or zip the Library/Mail folder to another drive to be even safer.

That said, I ran dozens of iterations of this solution against copies of my personal Mail archive without issue. And besides, if you’re reading this, you might not have any of your old mail, so how much worse could it really get?

If you’re still worried, copy your ~/Library/Mail/Mailboxes folder to another drive, run the script, then compare directories with something like Apple’s FileMerge. That will show you exactly which files have changed and what was changed inside them.

Renaming the attachment should be perfectly safe since the full encoded file contents are stored in the message. All the attachment name does is specify the filename, in a sense, it’s totally arbitrary.

I first submitted this bug with Apple back in May, if you have a developer account with Apple, please file a dupe for radar: 5912997

iPhone and the non-deleting email

I’ve seen this happen a few times, an email message just will not delete. Clicking the trash can shows the message delete animation, but the message just reappears behind the animation. The same thing happens in list view. The solution is to reboot the phone, everything should be fine after a restart.

To reboot the phone, hold the wake button for several seconds. A slider will come up asking you to power off. Shut it down, wait a second or two and then press wake to turn it back on. Your email should work normally.

I’ve found rebooting every few days is a good way to clear any slightly odd behavior or minor slowdowns. iPhone is a 1.0 release and these are software bugs. I’m confident they’ll be fixed in a future update.

Update: Force-quitting Mail can also help. To force-quit any iPhone application, just hold the home button for about 10 seconds, until the home screen displays.

iPhone vs. Apple Mail

I’ve been seeing an issue with Apple Mail affecting several iPhone users on a several different of hosts:

  • With a POP account, Apple’s will ask for the password repeatedly, refuse the correct password and fail to collect any mail.
  • With IMAP, the account seems to stall and does not necessarily update state or download new messages. Desktop IMAP behavior is particularly erratic.

In both cases, the iPhone continues to work just fine. The problems mostly affects users who’ve set their iPhone to Auto-Check for mail to something other than Manual. The following lines appear in the Desktop’s console.log almost immediately after setting the iPhone to auto-check for mail:

2007-07-05 15:33:17.190 Mail[21242] Unhandled response to command SELECT: * NO  Trying to get mailbox lock from process 28292
2007-07-05 15:34:24.098 Mail[21242] Unhandled response to command SELECT: * NO  Trying to get mailbox lock from process 29790
2007-07-05 15:36:14.917 Mail[21242] Unhandled response to command SELECT: * NO  Trying to get mailbox lock from process 31080

Those entries seem to indicate that the IMAP server is sending a response that Apple Mail doesn’t know what to do with.

A thread on the MacRumors forums claimed this was a multiple connections issue with the mail server, but I think I’ve conclusively debunked that, at least for IMAP.

To test the multiple connection theory, I set up Thunderbird on two other physical machines, one Mac and a Dell running Ubuntu, then set up my account using the default IMAP settings. I also opened my account in Horde webmail and hit reload a lot. Despite those simultaneous connections, Apple Mail seemed to be fine and messages were getting delivered. The little progress indicator was, however, still sitting there next to the account name, not spinning.

So now I can break Apple Mail just by turning on Auto-Check in iPhone’s Settings->Mail. Manual checking from the iPhone doesn’t cause any problems. So far I’m only seeing this on shared hosts running the Courier mail server.

IMAP is inconsistent about when it breaks, maybe relating related to server load issue. POP will break every time: If I check my email on a POP account with the iPhone, Apple Mail will immediately ask for and then refuse the password for that account.

An IMAP workaround

Installing IMAP-IDLE, pretty much fixes the problems with IMAP. I’ve had this running for several hours and the iPhone checking every 15 minutes, and things seem to be working smoothly. IMAP errors still appear in console.log but mail is getting through. I’m going to install this on a few other machines tomorrow and see what happens.

Not sure what to do about POP, but then we’re migrating everyone over to IMAP anyway.