I find below code or like in some sites (http://www.orcsweb.com/
articles/sending_smtp_authenticated_email.aspx)

my ISP announce that soon we need to give Authentication for sending
EMAIL. I add this code to my App, and I see that Even the Username &
Pass is not correct, the email send with no error. I try it with same
name & pass on OutlookExpress and I got Error. so it's seem to me that
this code not use with Credential that I give?


==================Heare the code
'Create a new MailMessage object and specify the "From" and "To"
addresses

Dim Email As New
System.Net.Mail.MailMessage("Brad.Kings***@orcsweb.com",
"B***@KingsleyTeam.com")

Email.Subject = "test subject"
Email.Body = "this is a test"

Dim mailClient As New System.Net.Mail.SmtpClient()

'This object stores the authentication values
Dim basicAuthenticationInfo As New
System.Net.NetworkCredential("username", "password")

'Put your own, or your ISPs, mail server name on this next line
mailClient.Host = "Mail.RemoteMailServer.com"
mailClient.UseDefaultCredentials = False
mailClient.Credentials = basicAuthenticationInfo
mailClient.Send(Email)

I check this code with account on Gmail and it's working.  the only
change I make for google is to add this line:
mailClient.EnableSsl = True

So my guessing that .NET check if server request login, and he send
the UseDefaultCredentials only if it request by the server. but the
Ouotlook express make login anyway. maybe this a reason that Ouotlook
express got error when the Password is not correct even server not
request login, but .NET send the email withoute error.

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