If you are trying to access your e-mail and get the error saying your password is incorrect don't worry as there is a simple solution.

1.Login to your CPanel
2.Click on Mail
3.Click on Add/Remove Accounts
4.Click Change Pass next to the account
5.Enter the password you wish to use (it can be the same as the original)

Your e-mail should now be working. This doesn't happen very often but for some reason passwords can get corrupt in CPanel. This shold solve the issue right away.