Authenticates a user towards the POP server using Auto.
If this authentication fails but you are sure that the username and password is correct, it might be that that the POP3 server is wrongly telling the client it supports Apop. You should try using Authenticate while passing UsernameAndPassword to the method.
|InvalidLoginException||If the user credentials was not accepted|
|PopServerLockedException||If the server said the the mailbox was locked|
|ArgumentNullException||If username or password is a null reference|
|LoginDelayException||If the server rejects the login because of too recent logins|