550 5.7.1 Mail Server sistemlerinde 550 5.7.1 hatasını alıyorsanız

Exchange Server 2003 için

Go in Administrative Groups -> Administrative group name -> Server -> Server name -> Protocols -> SMTP;

Right click on Default SMTP Virtual Server -> properties;

Access tab -> Relay buttom;

Select "only the list bellow" and add your domain and\or IPs you do want to allow the relay

Exchange Server

https://www.hakanuzuner.com/550-5-7-1/