Donald-0878 avatar image
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Donald-0878 asked Bruce-SqlWork commented

Error with Sending Mail via website

Hello Forum,
I need your help in resolving an issue I am currently facing. I cannot send mail from my website
to another email address. Before hosting my site, I tested it and it worked but ever since I hosted
my website it has not been working. I really do not know what could cause the error. All the login
credentials are correct but I keep getting the error. Please I really need help and direction to resolve this.
I am using office365 as my mail
Here is my code behind:

  using (MailMessage mm = new MailMessage("", mailtxtbx.Text))
             mm.Subject = "Account Activation";
             string body = "Hello " + txtname.Text.Trim() + ",";
             body += "<br /><br />Your Registration was successful.";
             body += "<br /><br />Please click the Button below to activate your account";
             body += "<br /><br /><a style='display: block; width: 130px; height: 15px; background: #355171;padding: 10px;font-family: Nunito; text-align:center; border-radius: 5px;color: white;font-weight: bold;text-decoration: none;' href = '"
             + Request.Url.AbsoluteUri.Replace("signup", "AccountActivation.aspx?ActivationCode="
             + activationCode) + "'>Click here to activate your account.</a>";
             body += "<br /><br />Thanks";
             mm.Body = body;
             mm.IsBodyHtml = true;
             SmtpClient SMTP = new SmtpClient("", 587);
             SMTP.UseDefaultCredentials = false;
             SMTP.Credentials = new NetworkCredential()
                 UserName = "",
                 Password = "xxxxxxxxxxxxx"
             SMTP.EnableSsl = true;

· 2
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This is error I got on my broswer

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mail-error.png (78.9 KiB)

Please investigate the difference in access right of the worker processes between the development environment and IIS environment.

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1 Answer

LanHuang-MSFT avatar image
0 Votes"
LanHuang-MSFT answered Bruce-SqlWork commented

Hi @Donald-0878,
You can try the following methods:

  • Check if the server OS hosting your website has a firewall rule to deny it.

  • You can check if something else is using the port with netstat:
    netstat -ano | findstr <your port number>

  • If nothing is already using it, the port might be excluded, try this command to see if the range is blocked by something else:
    netsh interface ipv4 show excludedportrange protocol=tcp

  • Try to restart the Host Network Service on windows service program.
    net stop hns
    net start hns

  • Restarting the Internet Information Services (IIS):

Best regards,
Lan Huang

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· 2
5 |1600 characters needed characters left characters exceeded

Up to 10 attachments (including images) can be used with a maximum of 3.0 MiB each and 30.0 MiB total.

All of the you mentioned, do I contact my host provider or do I effect myself?

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you contact your host provider to allow access to the port by your application.

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