Alternatives to Apple Mail

Question

Running Apple Mail is nothing but a headache since updating to Mavericks.
What are the suggestions for an alternative email client?  I've looked at Entourage and Thunderbird.  Frankly, I like the feel of Apple Mail better.
But I am having far to many problems with Apple Mail jumbling my various account's servers and settings.
Are there other email clients available that are reliable?
Thanks

Answer 1

If you have POP accounts you don't want to use Outlook 2011 for Mac.
Recommended: If you don't have Time Machine, backup your Mail folder by making a duplicate or copy to another location before doing the following.
Option 1) Re-index Mail.
Go to your User's Library folder. (if you don't know how to find, see this link http://www.needhelp4mac.com/2013/11/how-to-enable-users-library-folder/.)
Scroll to Mail folder.
Select the V2 > MailData folder.
Delete any files in MailData with envelope in the name. (should be 3)
When you open Mail it will re-index your files.
Removing accounts is not required, but for Gmail it's often the best option. Using Gmail with Mavericks Mail.
http://www.needhelp4mac.com/2013/12/use-gmail-with-mavericks-mail/
Option 2) This will nuke your current settings.
The following steps are similar to testing in a new User.
1)  Go to your User's Library folder. (if you don't know how to find, see this link.) Do steps a,b,c
a) Scroll to Mail folder.
Rename Mail OLD. [When you open Mail it will create a new Mail folder. You can revert to this folder if needed by removing OLD from the name. You would need to rename the "new" Mail folder first.]
b)  Go to Containers in the User's Library folder.
Delete the com.apple.mail folder.
c)  Go to Preferences in the User's Library folder.
If you find any com.apple.mail.plist files, delete these.
2) Log out under the Apple in the Menu bar. Log in.
3) System Preferences > Internet Accounts > Delete all accounts.
4) Open Mail.
5) Enter one account at a time. Test to be sure you are connected before adding other accounts.
If you have Gmail, be sure you have the All Mail folder selected to sync. Workarounds we previously used no longer work in Mavericks. You might need to go into your Gmail Settings in your browser to make the necessary changes. See this article for help:
Use Gmail with Mavericks Mail
http://www.needhelp4mac.com/2013/12/use-gmail-with-mavericks-mail/
If you have POP account you can import the "On My Mac" folders from the Mail OLD folder. If you have "leave on server" selected for your POP accounts, Mail will download all the old messages from the server. Compare the imported mailboxes to the Inbox and delete the duplicates. If you have moved messages to subfolders, I suggest you log into your account with your browser and move the old messages to a folder you create online. POP only downloads messages in the Inbox.