strange account names

What does “I just deleted some accounts” mean? How have you “deleted” them? What you’ve described indicates that you’ve just changed the settings of an existing account, but haven’t really deleted anything.

For each account, Mail creates a folder within ~/Library/Mail/ whose name starts with the Account Type (POP, IMAP, Mac), followed by the account’s User Name and Incoming Mail Server. If you later change those settings, however, the account folder isn’t renamed, and hence its name no longer matches the account settings.

If you want to set up a new account in Mail, you should actually create a new account rather than changing the settings of an existing one, but only if the new account is really different, i.e. if no other account has the same User Name and Incoming Mail Server. You should never, ever, set up two accounts in Mail with the same Account Type, User Name and Incoming Mail Server.

And beware that deleting a mail account in Mail (which is clearly not what you’ve done), causes the account folder and all your mail locally stored in the account’s mailboxes to be deleted as well. You can avoid mail to be lost as a result of deleting a POP account by moving it to custom “On My Mac” mailboxes -- and/or by making a backup of your data before deleting anything.

BTW, posting real email addresses in a publicly accessible forum such as this is a bad idea.

Well, Mail has to get the username and incoming mail server used to name the account folder from somewhere. I don’t see how Mail would create an account folder for a new account using the settings of an account that doesn’t exist instead of the settings of the account being created. If you didn’t modify an existing account, the only explanation I can think of is that you initially set up the new account with some wrong settings by mistake, then fixed them but the account folder had already been created.

Anyway, deleting the accounts and setting them up again should work. You may want to try again, maybe quitting Mail after deleting the account, then opening Mail and re-creating the account -- again, anyone reading this beware that deleting a POP account causes the mail stored there to be deleted as well.

Alternatively, you may try re-creating com.apple.mail.plist and getting rid of the wrong account folders as follows:

1. Quit Mail if it’s running.

2. Make a backup copy of the ~/Library/Mail folder, just in case something goes wrong while trying to solve the problem. You can do this in the Finder by dragging the folder to the Desktop while holding the Option (Alt) key down, for example. This is where all your mail is locally stored.

3. Move the wrong account folders to the Desktop, or just trash them if there is nothing to be preserved there.

4. In the Finder, go to ~/Library/Preferences/. Locate com.apple.mail.plist and move it to the Desktop (to be deleted after fixing the problem).

5. Open Mail. You’ll have to set up your non-.Mac accounts from scratch all over again. If given the option to import existing mailboxes or something like that, don’t.

You’ll have to re-configure most of your settings in Mail > Preferences. For spam-related security reasons, the first thing you should do is go to Preferences > Viewing and disable Display remote images in HTML messages if it’s enabled.

You may also need to re-install or re-enable any Mail plug-ins you have installed for Mail to recognize them.

6. As a side effect of re-creating com.apple.mail.plist, Mail might rename Outbox (which is where messages waiting to be sent are stored) to Delivered. The name of that mailbox is actually a misnomer, as it would contain messages (if any) that couldn’t be delivered for some reason. You can delete that mailbox if you wish.

7. If the old account folders had mail that you want to bring back into Mail, do File > Import Mailboxes, choose Mail for Mac OS X as the data format, and follow the instructions.

Note: For those not familiarized with the ~/ notation, it refers to the user’s home folder. You can easily locate any of the folders referred to in this post by copying the folder path here, doing Go > Go to Folder in the Finder, and pasting the folder path there.