Sending a mail or invite through asp - asp.net

Question

I'm trying to send email or invite dynamically using asp page.
I used,
Oapp = new Outlook.Application();
But the problem is when executed, the page tries to open a new outlook application and sends a mail. I want the page to use the existing or open outlook application and send a mail.
Can anyone help me???

Answer 1

Microsoft does not currently recommend, and does not support, Automation of Microsoft Office applications from any unattended, non-interactive client application or component (including ASP, ASP.NET, DCOM, and NT Services), because Office may exhibit unstable behavior and/or deadlock when Office is run in this environment.
If you are building a solution that runs in a server-side context, you should try to use components that have been made safe for unattended execution. Or, you should try to find alternatives that allow at least part of the code to run client-side. If you use an Office application from a server-side solution, the application will lack many of the necessary capabilities to run successfully. Additionally, you will be taking risks with the stability of your overall solution. Read more about that in the Considerations for server-side Automation of Office article.
As a workaround you may consider using EWS or Outlook API, see EWS Managed API, EWS, and web services in Exchange for more information.
For sending emails use System.Net.* classes for sending emails from the server-side.
public static void CreateMessageWithAttachment(string server)
{
// Specify the file to be attached and sent.
// This example assumes that a file named Data.xls exists in the
// current working directory.
string file = "data.xls";
// Create a message and set up the recipients.
MailMessage message = new MailMessage(
"jane#contoso.com",
"ben#contoso.com",
"Quarterly data report.",
"See the attached spreadsheet.");
// Create the file attachment for this e-mail message.
Attachment data = new Attachment(file, MediaTypeNames.Application.Octet);
// Add time stamp information for the file.
ContentDisposition disposition = data.ContentDisposition;
disposition.CreationDate = System.IO.File.GetCreationTime(file);
disposition.ModificationDate = System.IO.File.GetLastWriteTime(file);
disposition.ReadDate = System.IO.File.GetLastAccessTime(file);
// Add the file attachment to this e-mail message.
message.Attachments.Add(data);
//Send the message.
SmtpClient client = new SmtpClient(server);
// Add credentials if the SMTP server requires them.
client.Credentials = CredentialCache.DefaultNetworkCredentials;
try
{
client.Send(message);
}
catch (Exception ex)
{
Console.WriteLine("Exception caught in CreateMessageWithAttachment(): {0}", ex.ToString() );
}
// Display the values in the ContentDisposition for the attachment.
ContentDisposition cd = data.ContentDisposition;
Console.WriteLine("Content disposition");
Console.WriteLine(cd.ToString());
Console.WriteLine("File {0}", cd.FileName);
Console.WriteLine("Size {0}", cd.Size);
Console.WriteLine("Creation {0}", cd.CreationDate);
Console.WriteLine("Modification {0}", cd.ModificationDate);
Console.WriteLine("Read {0}", cd.ReadDate);
Console.WriteLine("Inline {0}", cd.Inline);
Console.WriteLine("Parameters: {0}", cd.Parameters.Count);
foreach (DictionaryEntry d in cd.Parameters)
{
Console.WriteLine("{0} = {1}", d.Key, d.Value);
}
data.Dispose();
}