Using Webbrowser control with Web proxy servers dynamically with C#

Question

I've been following this site with a lot of admiration especially on how questions are professionally answered so I decided to be fully involved.

Please, I need urgent help on a project that I have been working on for a long time but it's almost stalled now just because of a critical issue.

An aspect of the program automates email sending to clients using the free email server systems. Due to the high frequency of email sending, I observed that the email server we're sending to drops larger parts of the emails sent out and literally blocks delivery of major emails to the recipients.

I have tried to reduce the rate of sending email out but to no avail. My fear now is my IP address might have been blocked or may be blocked soon if this continue. The program is not spamming but have to be developed in order to contact a large database of recipients at a goal within short time - like about 1000 or more recipients.

I am using Webbrowser control in C# to automate the process of logging in to the mail server and sending the email out.

Now, what I want is a sample code to use publicly available web proxy servers for each email sent out such that the source IP address appears dynamic and different to the target email server each time a message is sent out to it.

I mean, I want to dynamically get and use free public proxy servers with the Webbrowser control to send out the emails. In this way I believe the email servers would not be able to reject the emails base on the IP address source. I want to know how to dynamically get literally one web proxy server for each email sent, if possible each time.

This project is very critical and this feature is a determinant. I have googled endlessly without any straight forward solution to this issue. I would, therefore, appreciate any useful help, sample codes or resources that could help me to solve this nagging problem once and for all.

Thank you!

Answer 1

Your problem is "free email server systems": they consider you a spammer, and the idea you suggest (spoofing IPs) will, if detected, ruin your reputation.

If you explain what you are trying to accomplish, perhaps someone here can offer a better design.

Are you trying to give people with free email accounts (like Hotmail) bulk-emailing capabilities?

Answer 2

First of all (if I understood your answer right), you don't have to use WebBrowser control - you can use specified .NET solutions that allows you to efficiently sending mails:

MailMessage msg = new MailMessage("from", "to", "subject", "body text");
SmtpClient client = new SmtpClient("smtp server");
System.Net.NetworkCredential cred = new System.Net.NetworkCredential("user", "password");
client.UseDefaultCredentials = false;
client.Credentials = cred;
Client.Send(msg);

Unfortunately, if you want to send e-mails to many recipients and you want to be sure, that these messages reach the recipients - you have to do it using your own e-mail server or do it by purchase the service on a paid e-mail servers - then they will not treat you as a spammer.

But if you anyway want to send e-mails by rotation proxy servers or similar sollution - you can define your proxy:

 SmtpClient client = new SmtpClient("my.proxy_server.com", 8080);

First you have to collect any list of available proxy servers which allows you to do it in reasonable time (servers switching can significantly increase total process time because conection time can be different for each proxy server)

Proxy servers list ordered by access time:

http://www.publicproxyservers.com/proxy/list_avr_time1.html