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Can i track the email is sent or not in c#?

I'm using SMTP to send the email, if the receiver email address is wrong then the email is not sent and no exception found.
So anyone helps me to find out the email was sent or not.?

Get Email Address from SMTP server by User name and password?

As titled, is it possible to get Email Address from SMTP server by User name and password?
The reason I want to do this is because I know some smtp server supports open relay and some don't, for that reason, I see no meaning to provide the Sender and From email address.
But in the SmtpClient class it requires a Sender and From Email email address.
Instead I want to do it by getting the actual Email Address which is the User name associated to in the SMTP server.
Is it possible to do this?

What is SMTP Server Address and how to get SMTP Server Address?

i am trying to send email from c# windows application and i need SMTP Server Address to send email but i don't know about SMTP Server Address, what is SMTP Server Address, how to get SMTP Server Address and how to use it.
this is the code:
System.Web.Mail.MailMessage message=new System.Web.Mail.MailMessage();
message.From="from e-mail";
message.To="to e-mail";
message.Subject="Message Subject";
message.Body="Message Body";
System.Web.Mail.SmtpMail.SmtpServer="SMTP Server Address";
System.Web.Mail.SmtpMail.Send(message);

What Mail Server are you trying to use??? usually you can just google SMTP or POP3 or whatever protocal your looking for and it will give you the port, server and all the extra information you need to connect to it.
For example:
http://support.google.com/mail/bin/answer.py?hl=en&answer=13287

First, the System.Web.Mail namespace utilities are marked as 'obsolete' and should not be used. Instead, you should use System.Net. In that namespace there is a 'MailMessage' and an 'SmtpClient' class that will do the job you are trying to do.
Next, an SMTP server is a process that runs on a computer, which, when connected to the inetrnet, can listen for, and respond to, incoming requests which use a particular protocol on a particular port. You can think of an SMTP server as the machine at the post office that sorts and routes the mail to the appropriate mailbox..
An SMTP server has an address, just like everything else on the internet that needs to communicate with anything else. The address is used to send your mail message to the right machine, on the right communication channel. you could think of it as its phone number, and your mail message a text that will be sent to it.
Next, the address you are looking for, last time I checked, was: smtp.gmail.com.
So, considering that you need to stop using System.Web.Mail, and considering that your address may be smtp.gmail.com, here is what your code should look like:
// setup mail message
MailMessage message = new MailMessage();
message.From = new MailAddress("from e-mail");
message.To.Add(new MailAddress("to e-mail"));
message.Subject = "Message Subject";
message.Body = "Message Body";
// setup mail client
SmtpClient mailClient = new SmtpClient("smtp.gmail.com");
mailClient.Credentials = new NetworkCredential("youraccount#gmail.com", "yourGmailPassword");
// send message
mailClient.Send(message);
Also, here is a decent looking article on using gmail as your smtp server:
How to use Gmail as your SMTP server
Also, if gmail does not work for you, you can use the smtp server of your internet provider. They will usually have their smtp address lurking on their website somewhere to be helpful to customers who want to setup their email program. You can also look in Outlook under account settings if you cannot find it somewhere else, if you use anything besides gmail, you should find one there.
Lastly, keep in mind, email cannot be sent without using an smtp server which is willing to receive and dispatch your maill message. In general this is something like gmail, or the smtp server of your internet provider, and the address will normally be: smtp.providername.com. However, gmail, for example, requires your account credentials for the smtp server to allow your message to be received and dispatched.

change sender address when sending mail through gmail in c#

I have used the following code to send mail from my web application using a gmail account. My question is, can i change the sender address to another address other than original sender(gmail) address?
My code is as follows:
System.Net.Mail.MailMessage mail = new System.Net.Mail.MailMessage();
System.Net.NetworkCredential cred = new System.Net.NetworkCredential("sample#gmail.com", "*******");
Whatever i do is useless as i always receive mail from sample#gmail.com. Is it possible to change it?
I have changed to
mail.From = new System.Net.Mail.MailAddress("sample#yahoo.com"); but i received the mail with the from address sample#gmail.com and not from the new "From" address. I think gmail smtp overwrites the from address with the original credential.

This is the solution:
use the codes above to set mail.From = new MailAddress(address, display name)
in Gmail, go to Mail Settings >> Accounts and Import.
Add the email account you will use as sender in "Send Mail As". (tick as Alias)
This works for me

Gmail doesn't allow you to change the FROM to something different than your gmail account.
It doesn't matter what you use, they over-write it, before they relay it on. This prevent spamming/spoofing.

Yes just use the From property of the MailMessage
eg.
mail.From = "newemail#email.com";
EDIT: Also, see this post for more detailed info on how to emails via gmail in C#
Sending email in .NET through Gmail
EDIT: Although this works for mail in general, it appears this won't work for gmail as google overwrite it before its sent (see #Dave wanta's answer)

If you have a limited number of senders you can do as #philip suggested. For instance you may have customerservice#example.com, simon#example.com and philip#example.com or even alias#example.com. As long as they are approved senders on the actual gmail.com website you can send from them.
Gmail.com : Sending mail from a different address
If you are expecting to send from an arbitrary user (such as a customer service form on a website where the user enters their email and you don't want them emailing you directly) about the best you can do is this :
msg.ReplyToList.Add(new System.Net.Mail.MailAddress(email, friendlyName));
If you're in a controlled environment this works great, but please note that I've seen some email clients send to the from address even when reply-to is specified (I don't know which).

Check #56 and #58. They might be relevant to what you want to do
https://code.google.com/p/google-apps-script-issues/issues/detail?id=172

Check if sender is valid with imap in C#

I know it is possible to send an email with a fake address to impersonate someone else. I seen automated emails coming from my friend email address that he sent to me but did not write himself.
I know email servers ask the email provider if they really sent the message and if it is no it tends to go into spam or is marked untrusted. How do i access this data in my app? I havent chosen an imap library and thats because i dont know which may support this.

This functionality is not supported by imap.
Some servers store information like this in the header of the mail (like spamassassin info or SPF checks) so that is available with any imap library but depends highly on the mail server the app is connecting to.

In general it's not possible with IMAP. IMAP is intended for reading email, not for sending. You may try to fake email sender when sending email via SMTP protocol.
This is exactly what spam senders do (and what mail servers tries to detected).
It used to easy. SMTP dialog follows:
S: MAIL FROM:<your.friend#example.com>
R: 250 OK
S: RCPT TO:<somene#example.com>
R: 250 OK
S: DATA
R: 354 Start mail input; end with <CRLF>.<CRLF>
S: Blah blah blah...
S: ...etc. etc. etc.
S: <CRLF>.<CRLF>
R: 250 OK
But now things are getting more interesting. There is still race of arms between those two - for example:
Attack
Try to submit false "FROM:" address during communication with SMTP server.
Defense: SMTP server may require you to authenticate and allow only 'from' address associated with your account.
Another attack
Try to use third party SMTP server that has no such rule.
Defense (third party SMTP server): Allow sending only emails with 'from' domains matches with 'own' domains.
Defense (recipient's SMTP server): Add SPF record to your domain. This records includes all hosts that are allowed to send email with sender in this domain. If the email is sent from not allowed host increase it's spam score or delete it.
Another attack
Infect computer which is allowed to send email for specified domain with virus and send emails using it.
Defense: Educate users and/or use good antivirus.
And so on... There will be always ways how to fake sender's email address and how to fake it. Check following links for more info:
RFC 821 - SMTP
So You'd Like to Send Some Email (Through Code)