I was working on an application which would send emails automatically at specific time intervals to a valid email. Searching through the internet I found that most of the codes use the existing email accounts such as gmail.com to send email by logging in as an SMTP client. But my problem is that I won't be knowing the smtp server name of the users email(since the user is not generally aware of these things though he will be knowing the login/passoword). For example,
someone#gmail.com should give smtp.gmail.com and port number (465)
someone#nextek.net should give mail.nextek.net and port number (?)
someone#screaming.Net smtp.tiscali.co.uk and port number (?)
I got the MX records using the domain name of the email address, but I realized that it actually gives the available incoming SMTP server names.
For example gmail.com would give gmail-smtp-in.l.google.com along with four other server name if I ping using nslookup in command prompt.
Also what is the advantage of sending email by using an existing SMTP supporting email than sending directly by looking up the email server name through dns? Or is it not possible?
Correct me if I am wrong, since I am not much familiar with the protocols.
If you're not familiar with the protocols, it doesn't make sense for you to try to implement the protocol.
Generally, an application like yours doesn't need to worry about the details of the SMTP protocol. You would use an existing SMTP client library for your platform (I'm sure there is one for .NET you can use), and connect to an MTA (your MTA, not the recipient's), give it the email to send, and you're done. The MTA will take care of all the SMTP protocol details of figuring out how to get the email to the recipient.
Sending email is very similar to dropping a letter in the post box on the corner, and letting the post office figure out how to deliver it. You don't need to know which vehicle to put it on, or where the recipient's local post office distribution centre is, or any of those details.
You may choose to set up your own MTA using something like Postfix, or you can send email through your own Gmail account (of course you'll need a Gmail account and password before Gmail will let you do that).
Related
I have several inquiry forms that I'd like to use a Gmail account to authenticate and send through. The forms send successfully, but the reply-to address is always the Gmail account, rather than the person's e-mail who filled out the form. This is a problem for the client in that they can't hit "Reply" without changing the reply-to address.
I've poked around the Gmail account and don't see anything that appears switch anything on and off to fix this. Any ideas?
My guess is that this is a restriction when using gmail as your SMTP server. You could use a different SMTP server to send the emails like MailDrill or MailGun.
OR
...and I'm not sure this will work. You can configure your gmail account to allow you to send emails with a different reply address/alias, but each address requires confirmation.
The steps to do this are located here
EDIT: I just re-read your message. Since you're using form data for the address I think your only option may be to use an alternate SMTP server.
Sorry I don't have a better answer.
I know there many articles on web regarding sending emails from code/C# and I have read many of them before posting here, but I still don't see a clear picture of how to implement my requirements:
Scenario:
My application on mydomain.com receives a request to send some kind of email (from: someone#mydomain.com, to: someone#gmail.com/anyother.com).
I need to make some manipulations on email content.
After I modified a message, I need to send it directly to recipient.
Under directly to recipient I mean that I want to send it to recipient by our servers and not using some kind of SMTP service/relay.
So as I understand I can install some SMTP software on our servers and send using System.Net.Mail.SmtpClient to our server and it will deliver it to recipients using SMTP Relay or some other way that coded inside that software...but, I would like to make it without using SMTP Server software...
Till now I found that I need to discover MX record for recipients domain, so let's say I found MX record for gmail.com (gmail-smtp-in.l.google.com), but how do I send email to that MX Record from my own C# code?
Does System.Net.Mail.SmtpClient suitable for this task?
Where I can find examples of how to do it?
From my previous expirience with SmtpClient, I need to provide SMTP server address (optionaly port), credentials, but in my case, of course I do not have credentials and I'm not sure how to get the correct port (does all servers from MX records has port 25?).
Thanks!
I want to send an anonymous email to my own gmail/hotmail/yahoo/any other mail service address (Im not trying to spam or something like that).
Why? I have a .NET application and I want to add a "Send log to the developer" feature (attaching the log) using SmtpClient. The fact is I've read like 30+ pages, and found out, i.e. gmail's smtp client doesn't allow anonymous connections, and many other things.
The idea is to receive a mail message like this:
From: logs#myapp.com (non-existent email really)
To: myrealaddress#somedomain.com (this would be my real address which will recieve the logs attachments)
Subject: Issue report nºX (auto-generated)
Body: From a textbox
Attachments: logs attached
Is this possible? If so, how do I achieve it?
The short answer is that you can't reliably achieve this. You can get it to work in some cases, but not all.
Most email servers these days have spam filters and rules for checking on emails, and in most cases an empty 'From' address will result in special treatment. Sometimes that just means a slightly higher spam score from the receiving mail server, but in some cases an empty 'From' address will result in your email being silently dropped in the bit bucket. You have no control over this, and neither will your users. It's all down to how the receiving mail server is configured.
The simplest option is generally to allow the user to configure a from address and SMTP server. Some servers will require login to send messages, so you have to consider that. Many ISP mail servers (and most internal workplace mail servers) don't require login if the connection is coming from an address owned by the ISP (or workplace) and the email address is one that is registered as belonging there. Some ISPs - and this number is apparently growing - require SMTP login to send mail regardless.
Another option is to set up a source domain, configure the SPF record for the domain to allow email from any IP address, and use a standard 'From' address in that domain. The downside to this is that once someone discovers that you've opened up a domain that way they'll start using it to send spam and you'll get shut down.
There are many other options that have their own problems. One of the problems is that they generally cost money - some setup costs, most options also with ongoing costs - or open you up to liabilities of some sort.
Give your users the choice. Let them try various options and see what works for them: no 'From' address, user-defined 'From' address (same as 'To' address is a good first try), partial SMTP login, full SMTP login, etc. If they don't trust your code enough to put their passwords in, let them create a throw-away account on gmail or something to run the messages through.
I'm a big fan of the email feature available in Backpack, where it creates a unique email address per backpack page, and any emails sent to that address will be posted to the page.
My question is about how best to go about creating new email addresses automatically, and listening for new emails sent to those addresses. I'd like to do this from a C# service (I'm not using ASP.Net)
Has anyone tried to achieve this or
something similar before?
Are there libraries (preferably
FLOSS) already available which do
this or would assist me?
Is it possible to do this using a cloud-based
email service (and if so, what service?) and a
library for communicating with that
service (OpenPop.Net or similar)?
If your email provider supports setting up wildcard email on your domain, then you can do this with a single email account.
For example, Google Apps for Domains allows setting *#example.com to be delivered to myaccount#example.com. When someone emails sales#example.com or contact#example.com it will all be delivered to myaccount#example.com.
Then it's a process of getting all the emails. You then look at the to header in the email, match that with the name stored in your application for that user, and then process however you wish.
Be aware that you will get spam and other incorrectly addressed emails when you use this method. You will have to deal with these yourself (eg by discarding incorrectly mail that isn't addressed to a valid account).
I haven't played around much with incoming mails, but from the top level here is what you should do.
Create email addresses for the users based on any logic and save it in the DB.
Setup a mail server with your domain name and set one email account as a "catch-all" mail account. Any mail sent to your domain would then be caught under that mail account, in case the email address is not found.
Create a windows service, that would read mails from that "Catch-All" account. There are several libraries available to read mails using POP3 or IMAP.
Read the incoming mails to check the email address it was sent to, compare it with the values stored in the DB and process accordingly.
Check this question. it might help you with reading incoming mails.
The objective isn't to create email addresses, that doesn't really happen. What you do is accept email addresses at your system, what you accept is up to you. You could set up a mail server to receive any email sent to your domain, you could then parse the email To field and extract the 'name' portion. If it matches something you are listening for then you action it accordingly.
I don't think you'll find a library for this specific activity as it's rather insular. There are plenty of ways of receiving emails directly or indirectly and processing them in C# but I won't cover that as mail handling in .Net is well documented.
Is it possible to send an email in C# console, without needing and SMTP server?
Edit:
Why do I need another SMTP server? Can not I use my localhost machine as a server..?
Edit:
I just need to send an email from with my domain name, for example abc#mydomain.com
Is that possible? what do I need to do this in my C# program... I do not care about receiving emails, I just care about sending them....
Thanks
You don't have to depend on a local SMTP server if you don't have one. However, you will have to connect to a SMTP server anyway. Here is why.
You must achieve the following steps:
Determine what is the mail exchange servers of a given domain.
Connect to that mail exchange server and deliver your mail.
Those steps are normally done by your local SMTP server. Another advantage of your local SMTP server is that it will handle its queue and continue to try to deliver your email if it fail.
How to determine the MX records of a give domain.
I suggest you to have a look at this answer. Basically, you have to do a query on a DNS server to get the list of MX records of the domain name of the email address you want to send an email to.
How to connect to a mail exchange server
Well the answer will disappoint you. Exactly like you connect to your local SMTP server. Using the TcpClient, you connect to one of the mail exchange server you got at the previous step on port 25 and start the delivering process using the SMTP protocol.
The trick here is that you must handle multiple MX servers. They are usually listed with a preference. If the first one is unreachable, you try the next one and so on...
That is something your SMTP server can handle for you too.
If you really want to build that logic yourself, please have a look at the DirectSend method of the SmtpClient class of this open source project I'm involved in.
As #TomTom points out, the entire mail infrastructure depends on SMTP. What you can do is to skip the output (relaying) SMTP server and send the message directly to the receiving SMTP server.
To do that you need to create some kind of queuing mechanism (there is no guarantee that the receiving SMTP server can serve you when you try to connect) and that you can look it up.
MX records are entries stored in DNS servers and are used to find SMTP servers. You can find a article here with a MX lookup example: http://www.codeproject.com/KB/IP/dnslookupdotnet.aspx
However, I DO recommend that you install a local SMTP server and let it take care of the above mentioned issues.
Yes, Basically figure out where to sent the email and send it. i.e. a DNS MX lookup for the domain to find out the SMTP server.
Every email needs an SMTP server on the receiving side.
You can use gmail or yahoo SMTP server, if you don't want to install your own.
Before sending mail you first need to authenticate, otherwise sending mail is not going to possible.
You need access to some kind of email server to send your email, and your email will most likely pass through one or more SMTP servers on it's way to the recipient. However, the email server you connect to might let you send the email without using SMTP. For example, Exchange might let you use MAPI or CDO to send emails. Though I think that CDO is not officially supported by .Net and simple MAPI is deprecated in Windows and should not be used. You might be able to use Exchange Web Services as described here: Introducing the Exchange Web Services Managed API 1.0
If you have another email server than Microsoft Exchange, that server might have some kind of API you can use.
Something I do often is to create gmail account and send through that account.
You just need your SmtpClient to connect to the host smtp.gmail.com on port 587 with the username, password, and enableSSL property set to true.