Unable to delete IMAP mail account in Yosemite

I have an IMAP mail account in the Apple Mail client that I want to delete. I first goto the Accounts preferences pane in Mail. When I click the minus icon to delete the account, I get a message about having to do it in Internet Accounts.

However, when I goto Internet Accounts, the email account isn't listed. I see all of my mail accounts except for this particular one.

How can I delete this mail account?

Solution 1:

This is not my Fix I found it here

Find and Open the Folder Where Mac OS X Mail Stores Mail. To open the folder where Mac OS X Mail keeps your messages:

1. Open a Finder window.
2. Select Go | Go to Folder… from the menu.
3. Type ~/Library/Mail/V2

Delete all the folders and files in this directory

Find and Open the Folder Where Mac OS X Mail Store Mail. To locate the folder where Mac OS X Mail stores mail:

1. Open a Finder window.
2. Select Go | Go to Folder… from the menu.
3. Type ~/Library/Mail/

Delete the folders. Now all the Accounts will get deleted from mail