Why do I get "'property cannot be assigned" when sending an SMTP email?

mail.To and mail.From are readonly. Move them to the constructor.

Why do I get "'property cannot be assigned" when sending an SMTP email?

mail.To and mail.From are readonly. Move them to the constructor.

using System.Net.Mail;

...

MailMessage mail = new MailMessage("you@yourcompany.example", "user@hotmail.com");
SmtpClient client = new SmtpClient();
client.Port = 25;
client.DeliveryMethod = SmtpDeliveryMethod.Network;
client.UseDefaultCredentials = false;
client.Host = "smtp.gmail.com";
mail.Subject = "this is a test email.";
mail.Body = "this is my test email body";
client.Send(mail);