Sending mail using SmtpClient in .net

Question

I am unable to send the mail using smtp client. here is the code:

SmtpClient client=new SmtpClient(\"Host\");
client.Credentials=new NetworkCredential(\"username         


        

Answer 1

I figured out that setting the SmtpClient Credentials property before setting the ' UseDefaultCredentials = false ' UseDefaultCredentials = false causes the credentials to be ignored.

Fails:

SmtpClient smtp = new SmtpClient;
smtp.Credentials = new NetworkCredential("user","pass");
smtp.UseDefaultCredentials = false;

Works:

SmtpClient smtp = new SmtpClient;
smtp.UseDefaultCredentials = false;
smtp.Credentials = new NetworkCredential("user","pass");

Go figure.

** UPDATE **

The reason the order is important here is that the setter on the UseDefaultCredentials property actually sets the Credentials to null via the decompiled code:

/// 
Gets or sets a  value that controls whether the  are sent with requests.
/// 
///  if the default credentials are used; otherwise . The default value is .
/// You cannot change the value of this property when an e-mail is being sent.
public bool UseDefaultCredentials
{
  get
  {
    return this.transport.Credentials is SystemNetworkCredential;
  }
  set
  {
    if (this.InCall)
      throw new InvalidOperationException(SR.GetString("SmtpInvalidOperationDuringSend"));
    this.transport.Credentials = value ? (ICredentialsByHost) CredentialCache.DefaultNetworkCredentials : (ICredentialsByHost) null;
  }
}