MailKit在收取163邮件时发生异常：
MailKit.Net.Imap.ImapCommandException: The IMAP server replied to the ‘EXAMINE’ command with a ‘NO’ response: EXAMINE Unsafe Login.
解决方案：
添加邮件客户端识别
var client = new ImapClient()
var clientImplementation = new ImapImplementation
{
Name = "MailKitDemo",
Version = "1.0.0"
};
var serverImplementation = client.Identify(clientImplementation);
