Task DisconnectAsync( bool quit, CancellationToken cancellationToken = null )
|ObjectDisposedException||The IMailService has been disposed.|
|ServiceNotConnectedException||The IMailService is not connected.|
|OperationCanceledException||The operation was canceled via the cancellation token.|
|IOException||An I/O error occurred.|
|CommandException||The command was rejected by the mail server.|
|ProtocolException||The server responded with an unexpected token.|
Asynchronously disconnects from the service.
If quit is true, a "QUIT" command will be issued in order to disconnect cleanly.