As part of my app's config process, I have a sanity checker that validates all user-supplied data. This includes email server settings that the app uses to send email.
I'd like a simple sanity check on those settings without actually sending any email. It'd be great if this could support all standard flavors of SMTP setups including those with authentication/ssl/etc.
It doesn't need to be exhaustive but the more coverage, the better.
Currently all I do is verify I can open a connection to the given server on the given port. Something a little deeper would be nice.
Note: I'm not trying to validate email addresses--that's not relevant to this question.
You just open a raw connection to the server & port that the user supplies and do a
HELO Server.Domain.Com
Mail From: validaccount#domain.com
to see if you get a valid HELO response & Sender OK Response
(if smtp authentication is enabled).
Same as you would do if you telnet direct to the server.
http://www.petri.co.il/test_smtp_service.htm
This might also be useful
http://qmail.jms1.net/test-auth.shtml
I'm sure someone brighter and more qualified will pipe up with a better answer. However, at first blush I'd say that you cannot verify the ability to successfully send email without actually sending an email.
However, if you want to automate the process, you can have a 'MyApp_SanityCheck#gmail.com' (or your local domain) address.
Then you can create a watchdog application that monitors that email address, or just a simple app which programmatically interfaces with that email address and checks if an email was received within X minutes. This way you can be 100% certain that the emails are able to be sent out.
This link shows how to programmatically check gmail addresses.
An important note: If you application is sending out external emails, then it would be best if the email address you use is external, because it is possible that your server could be unable to send external emails, but internal emails go through just fine, and in that case your sanity check would send up a false positive.
Related
I work with a dozen pieces of equipment whose operating software has the option to send e-mails on error. I would prefer to capture the details of that e-mail on the host PCs that run them (i.e. for logging, communicating details automatically via Slack, etc.) rather than them going to an inbox somewhere.
Is there a way to have the software e-mail an address that is essentially a lightweight piece of code running on the same PC mimicking something like an SMTP server (that will allow me to get after the message's contents)? Other solutions I have seen are along the lines of setting up a full-blown server which seems like overkill.
You may configure SmtpClient to save email to a specific folder instead of sending it over the wire. Check this answer.
Also you must design your system in the way it could work with different implementations of your 'sender', so that you can replace it when you need that, for example during testing. In this case you can easily provide proxy implementation that will capture email content and then send it to localhost, or add aspects (make retries, logs performance...).
I am Creating an application in c# . I have to know how can I know the status of the sended email.The status May be.
4. Track sent emails to determine if they were:
4.1 delivered
4.2 opened
4.3 recipient opt-out
4.4 bounced (with the reason for the bounce)
4.5 time/date sent
4.6 which links in the email were clicked (and time/date they were clicked)
4.7 IP address, if user clicked any links in the email
Should I use Any API or Dll or something else.Please help .Any Help will be Appreciated.
If you program your application to send mail through a hosted SMTP server like http://www.sendgrid.com or http://www.ultrasmtp.com, you can access the delivery status of messages that you've sent.
There is no easy way to do what you want. Actually this status can be tracked by your SMTP server itself and if you are using some third-party SMTP server like GMail or any corporate server, I 'm afraid they won't give you access to those information without using a authenticated client.
From your C# program, if the SmtpClient.Send() method returns true, you can assume the mail has been delivered to the SMTP server. If in case, the delivary fails, you should receive a mail to the outbound mail ID's inbox. If you want to make outbound mails appear in your outbox, you should configure IMAP/POP3 configurations accordingly.
There is no API or DLL available in exact form you want, as far as I know. You can try some other way like tracking a hash or embedded image in the mail-body from your server. But these are not reliable way as most mordern Messaging services have counter-measures for this.
I have a date picker and time picker in my app and I'm trying to send mail as described here which contains the date as well as the time in the body of the mail.
So, Now my question is how to disable the body part of the email as the user shouldn't edit the date or time once it is selected from app.
What's the point of security in this ?
Code:
var mailto = new Uri("mailto:?to=me#mysite.com&subject=Date Selected :+datepicker.value+");
await Windows.System.Launcher.LaunchUriAsync(mailto);
The way you decided to generate the email, you don't have any control over the email client from that point on - you have called an external process and passed your parameters to it. The user could do with that email whatever he wanted or even delete it without sending, without you knowing about it. Also you are depending on the user having the system setup correctly for this link to work.
To keep control over the email you are sending you shouldn't depend on external applications, therefore the solution with sharing won't help you either, even though it's prefered in Windows Store apps over the one you are currently using.
If you really need to have the email sent unchanged, you only have two options:
Use a client side SMTP library for sending emails. The only one I know of for Windows Store apps was released by Limilabs. The downside is that you need to configure your app locally with SMTP server settings.
Send a request to a web service and send the email from there. This is probably the best approach, since it is completely under your own control and doesn't require any additional configuration on the client side.
AFAIK you cant disable the recipient, subject or body of an email.
If you want to detect an edit, then you can add a checksum to the body.
We have a website sending mail alerts to end users. The site has been developed in c# ASP.NET.
I want to find the best way to send the email alerts to my users. Making sure the mail is not trapped in any spam filters. I read on the internet it is best to sent the mail directly from the web server and not route via an SMTP mail service such as google apps or Postini.
Can anyone tell me if this is correct?
First of all
Making sure the mail is not trapped in
any spam filters
Is not possible - otherwise spammers would do this. You just have to make sure you're domain isn't associated with any spamming activities and watch for keywords within the email.
I read on the internet it is best to
sent the mail directly from the web
server and not route via an SMTP mail
service such as google apps or
Postini.
This point doesn't make sense - your e-mail will never be delivered if it doesn't get routed via an SMTP server, the average message will pass through multiple on its route to the recipient.
The answer is to not actually send email and let someone else deal with the problem. I'd look at postmark or Amazon's simple email service.
We had problems that mails sent with local server often get trapped in spam filters until we implemented SPF on our mail server.
http://en.wikipedia.org/wiki/Sender_Policy_Framework
But I am not admin, that's just what our admin said, and after that we have no problems anymore.
btw. maybe would be better to ask on serverfault.com
I have an application with a static class that is capturing all errors that happens during the runtime (if its the case) and when process is done, it sends out an email with the list of errors so I or any other developers can address those errors.
However my problem is that McAfee is blocking the request, as if it was a kind of virus. I do not have rights on my machine to edit McAfee settings, is it possible to fix it through C# code?
Thank you
Probably McAfee is blocking outgoing connections on port 25 (SMTP), only allowing a white list of applications to send email.
What you can do is:
Put the email in a mailto:// url. Execute the mailto:// as if it is a normal command line. This will ask for input from the user, but you can create a nice template for the user. (syntax)
Send the email through your normal email client (Outlook, Notes), if they have an API for that.
Use a Http/Web based provider that has an API. Public ones are probably also blocked by McAfee. But you could create & host a service yourself. Be very carefull to only allow traffic from within your company.
Maybe you company has a "drop folder", where you can drop emails that are picked up by the email server.
Depending on what/why McAfee is flagging it, more than likely you will not be able to get around it.
You will want to see if you can find out if McAfee is flagging it due to the port being used, or if there is any other information as to why the individual message is not going.
No. And yes.
No, you can't force McAffee to not flag your email from code, if that's what you mean.
Yes, you can prevent McAffee or other virus scanners from flagging your emails as suspicious. Here are a couple of things I try to make sure of:
That your all addresses (especially from: and reply-to:) are valid.
That the the name you're sending from is actually the name of a the correct person in your active directory.
You could also ask your system administrators to put your "from:" address on a global whitelist so that it always goes to the client.
Are you attaching executables? Are you sure you aren't attaching any viruses? ;-)
From what I recall, I think McAfee has a list of programmes that are allowed to send emails, if your program is not added to this list, then your emails will not get sent.
This is a big support problem, as you will find your customers have a 101 different virus checkers all setup in different ways.
You may be able to setup a email server to use a none standard port, then send emails to that port.
For testing, attaching to the McAfee process with a debugger and then killing it can work well...