Can't open Mail, Index is broken!

Question

Hi, I need some help.
I don't use Mail on my iMac or Macbook Pro Retina but need it to run some AppleScripts, so I tried to open it on my Macbook Pro Retina and iMac but can't open it on either, it just comes up with the below:
First:
To use the new features in Mail, your existing Mail messages need to be imported into the new version the first time you use Mail. this might take a few minutes. You won't be able to use Mail until the import is finished.
Click Continue to import your messages now, or click Cancel to import later.
If you click cancel, it just closes and if you click continue it does the below:
The Upgrade Failed
An error occurred during the upgrade. Click continue to launch the Mail Import Assistant, which will help you create a new library and import your existing messages.
So I then click continue and this is what appears:
You Mail Index has been damaged. To repair it, quit Mail.
Mail will repair the index the next time you open Mail. Your mailboxes and messages will be preserved.
So I then click Quit. It shuts down and then if you try to open it again, it just does the same thing again and again.
I have managed to fix the one on my Macbook Pro Retina by following what some people suggested on other posts, what worked was deleting the com.apple.mail folder inside Library/Containers. And I haven't had a problem since but with the iMac once this file is deleted, it allows you to go through the whole set up for a new account and then goes into the same error pattern as mentioned above. I have also tried deleting the Envelope Index inside Library/Mail/V2/Mail Data and in the Mail folder too, but nothing seems to work.
Can someone please adivse as to how I can re set my Mail, there is nothing in there so it can be rebooted or something like that. I just don't understand why I have managed to fix in one computer and not in the other one !!
Any help would be much appreciated.
Thanks,
Sally

Answer 1

Quit Mail. Then select
 ▹ Force Quit...
from the menu bar. A small window will open with a list of running applications. Mail may appear in that list, even though you quit it. If so, select it and press return. Close the window.
In the Finder, hold down the option key and select
Go ▹ Library
from the menu bar. Move the following items from the folder that opens to the Trash (some may not exist):
Caches/com.apple.mail
Saved Application State/com.apple.mail.savedState
Application Support/AddressBook/MailRecents-v4.abcdmr
Containers/com.apple.mail
Mail
Preferences/com.apple.mail.plist (OS X 10.7 only)
Preferences/com.apple.mail.searchhistory.plist (OS X 10.7 only)
Note: you are not moving the Mail application. You’re moving a folder named “Mail.”
Log out and log back in. Launch Mail. It will behave as if you were running it for the first time. Go through the setup process with one of your accounts.