Although my password is correct when reading mail with POP3, I get the error -'ERR Logon failure: unknown user name or bad password' in MICROSOFT 365 mails. I can read all other mails but I have problems with microsoft 365 mails.
Version update , I did tls updates
List<MailMsg> mailMssgList = new List<MailMsg>();
ServicePointManager.Expect100Continue = true;
ServicePointManager.SecurityProtocol = (SecurityProtocolType)3072;
ServicePointManager.SecurityProtocol = SecurityProtocolType.Tls|SecurityProtocolType.Tls11| SecurityProtocolType.Tls12|SecurityProtocolType.Ssl3;
Pop3.Pop3Client pop3Cli = new Pop3.Pop3Client();
pop3Cli.Connect(SERVER, USERNAME, PASSWORD, PORT, SSL);