I find the best thing usually depending on how much email there is, is to just forward the mail through your ISP's SMTP server. Less headaches. Looks like that's where you are having issues, from your SMTP to external servers, not asp.net to your SMTP.
Just have your SMTP server set to send it to your ISP, or you can configure asp.net to send to it.
EDIT: I use exchange so it's a little different, but it's called a smart host in exchange, but in plain SMTP service config I think it's called something else.
I can't remember exactly the setting name.
CVertex, make sure to review your code, and, if that doesn't reveal anything, post it. I was just enabling this on a test ASP.NET site I was working on, and it works.
Actually, at some point I had an issue on my code. I didn't spot it until I had a simpler version on a console program and saw it was working (no change on the Gmail side as you were worried about). The below code works just like the samples you referred to:
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Net.Mail;
using System.Net;
namespace ConsoleApplication2
{
class Program
{
static void Main(string[] args)
{
var client = new SmtpClient("smtp.gmail.com", 587)
{
Credentials = new NetworkCredential("myusername@gmail.com", "mypwd"),
EnableSsl = true
};
client.Send("myusername@gmail.com", "myusername@gmail.com", "test", "testbody");
Console.WriteLine("Sent");
Console.ReadLine();
}
}
}
I also got it working using a combination of web.config, http://msdn.microsoft.com/en-us/library/w355a94k.aspx and code (because there is no matching EnableSsl
in the configuration file :( ).
2021 Update
By default you will also need to enable access for "less secure apps" in your gmail settings page: google.com/settings/security/lesssecureapps. This is necessary if you are getting the exception "`The server response was: 5.5.1 Authentication Required. – thanks to @Ravendarksky
Best Answer
We have seen this issue before on one of our test servers.
It turned out that an IIS update/windows Update caused an issues with an out of date Anti Virus Email Scan engine. Even though the anti virus patterns were up to date the scan engine/av program was old and causing the SMTP service to hang and crash.
Hopefully this is the same issue for you.