How to avoid to be considered spammer on a dedicated server? - spam

I have a dedicated server, with few small projects as a corporative local websites for local companies in south spain.
In the past, with other dedicated server, all the emails were considered spam, even in the first email they send. The IP is not blacklister.
How can I do to warranty that our emails are not going to be spam anymore? I hear / read something like I have to sign the emails or pay a kind of montly fee to get some kind of certificate.
Someone can help me please?
Thanks a lot!

Try this webpage: http://isnotspam.com/
You send an email to the address that they give you, and they will tell you why your message is flagged as SPAM.

Related

i received an email(gmail),how to know senders IP address if both sender and receiver uses same domain

using email analysis we can find senders IP address through some tools only if they are from different domains like senders sends from yahoo mail to gmail user.
How to find senders IP if they are from same domain?
example:
from: abcd#gmail.com
to : wxyz#gmail.com
while in email analysis iam getting senders IP as google servers IP
What you can actually achive with any tools depends very much on whose IP address you want to find out:
If you want to get the address of the client, on which a user probabply typed the email and from which it was transferred to its provider's Mail User Agent (MUA), forget it. As long as you are not a government with the appropriate court decision or very good friends with the server operator, the latter one will not give you even slightly sensitive information about its clients, also not the IP address.
If you want the IP address of the MUA of the client's mail service provider, you have much better chances. Assuming that the from field is correct, then just check out which addresses this provider uses. Gmail has probably a lot of various server machines and I think you might not find the exakt IP of the server the sender's client connected to. If the from field is manipulated (junk mail), Gmail's Mail Transfer Agent (MTA) will probably reject the mail, so that it will never arrive in your inbox anyway.
The sender and the recipient may use different mail service providers, in that case your provider's admin could have a look into the server's log files to find out from which IP address the recipient's provider's MTA was connected. However, usually this is absolutely irrelevant, as long we are dealing with two respectable organizations. Also you explicitly mentioned that in this scenario, it is one and the same provider.
Finally, you can find out the address of your own MUA, but I think that has nothing to do with the author of the email.
So, in conclusion: technically you can't. The only really interesting information is the address of the client used by the author of the email. Google is a respectable enough company to never ever give this information to you, except if the sender's mail client explicitly wrote it into the mail header, which it probably never will.
If you want the IP address because of criminal activity or any kind of abuse by the sender, just contact Gmail. If that does not help, file a lawsuit. The latter one may actually take a long breath until you (may!) be successful, so be sure if your situation is really that bad.
However, if you have a lot of criminal energy you could use the more general metadata from the header to create a profile of the sender's client, like which client software of which version he*she uses and more. But I think this is going to be very, very much work until you get more relevant information (and it should be).
It would actually be very helpful to have a few more information on your scenario, e.g. what you need the address for, if you really mean the client's address or the mail provider's server address, how much work you are willing to invest and also which kind of mail service provider we are talking about. If you run your own mail server, you suddenly gain access to a lot of interesting information...
Feel free to clarify your needs, so maybe someone can help you better. Also, I hope I didn't hit you with too many words, I am new and excited about stackoverflow ;)

IIS SMTP used to relay Contact Us form messages to Gmail has been blacklisted by Google

I have 2 Windows 2008 R2 boxes running in Microsoft Azure. My ASP.NET 4.0 site (let's imagine it's running at "example.com") has a standard Contact Us form.
When a user sends a Contact Us message, I use System.Net.Mail and SmtpDeliveryMethod.Network to deliver mail to an IIS6 SMTP server running on each box, which sends the mail to a Google Apps "enquiries#example.com" account, using the email address the user entered into the Contact Us form as the "From" address.
This was working beautifully for a year until I checked it today, and found this error in a .BDP file in the \Badmail folder:
550-5.7.1 Our system has detected an unusual rate of unsolicited mail originating from your IP address. To protect our users from spam, mail sent from your IP address has been blocked. Please visit http://www.google.com/mail/help/bulk_mail.html to review our Bulk Email Senders Guidelines.
Obviously Google upped their anti-spam strategies in the last 6 months - last time it worked was Feb 2013 (yeah, we don't get much mail luckily... yet).
I've read the Bulk Senders Guidelines linked above, but they're not really suited to my use case. My case is not sending emails from our server to users of our site (I simply use the Gmail API and send from our enquiries#example.com for that), but rather to collect users' enquiries so that we can easily respond by clicking Reply in that inbox.
I am looking for the easiest solution here. In response to the ones in Google's Bulk Senders Guidelines:
Use a consistent IP address to send bulk mail: I already do, doesn't seem to help
Reverse DNS: Godaddy, my domain and DNS provider doesn't seem to support them: http://support.godaddy.com/groups/domains-management-and-services/forum/topic/how-do-i-setup-reverse-dns/ Anyone know if there's a way?
Use the same address in the 'From:' header on every bulk mail you send: This is totally not my use case. I'll have different From headers in every email
SPF record: I think this only works if I am sending From ...#example.com every time. Is that right? My feeling is SPF doesn't help me here. Would love someone to enlighten me.
DKIM: This looks hellishly complicated, but I'll pursue it if someone thinks it can work in this case. Specifically is it OK that the From address doesn't match the "signing domain"? Anyone got any good "how to" links? And will this be sufficient for Google to un-blacklist me?
Sendgrid: Azure's preferred mail sending app. This means signing up, code changes, testing, and unknowns like "does Sendgrid allow any From address? It's non-trivial, and I'd like to avoid this, but again, will go there if it's what people think is the sanest option.
As a general answer to your questions, sending email on behalf of many different domains from one IP (e.g. example.net, example.org, and ex.co from 10.0.0.1) is generally seen as spammy behavior (and therefor not recommended).
Your points 1-5 only apply if you're sending from one domain. rDNS, SPF, and DKIM only improve delivery for one IP to one domain (in a generally 1:1) relationship.
Generally, the best way to avoid getting marked as spam in a situation like this is to set the From email as a consistent one that you actually control (e.g. enquery-sender#example.com), and then setting the Reply-To as the entered address (e.g. enquirer#someprovider.com). This way you consistently send from one domain, while still getting the benefit of replies going to the message originator (for example LinkedIn does it this way). Doing this will allow you to setup rDNS, SPF, and DKIM with benefit.
That said, if you decide that you don't want to use the recommended Reply-To method, you can use SendGrid to send from any arbitrary domain. It should not require any significant code change (just switching your current SMTP credentials to SendGrid's).
Disclaimer: I am a SendGrid employee.

https and SSL can protect your mail address from being harvested and used as spam?

I manage a googlegroups with many hundreds of people, and often happens that spam is sent to our mailing list even if it's for members only.
The most annoying is when the spam arrives with the address of members.
Which suggestions can I give to the people to reduce the risk of their mail being harvested by spam bots? I usually suggest to enable https on their webclient and SSL on their desktop client and to run an antivirus session regularly.
Is this a good way to avoid the problem or it doesn't change anything?
No it is not. Neither of your recommendations have anything to do with spam bots harvesting mail addresses. Those are normally scraped from a website/number of websites. The best advise you can give them is never to post their emails to a website pernamently, or use something to confuse the bots, such as [ad] instead of #.
Also as you can spoof the address of the sender, you pretty much can't avoid spam sent with sender address of the members, once they have those addresses (e.g. I get even spam from my own address).
There is hope!, as Cyber-Guard Design proposed ask your users to not write down their mail addresses normally. For example normally you would write ur mail adress like
myname#somedomain.com insted do => myname[a_t]somedomain[d_o_t]com
That should do the trick, for most bots at least

How to validate the ownership of the website?

e.g. Google Webmaster Console does it by asking website owners to upload a file with specific name. Other services use the same approach.
Is there any reason why not verify ownership by simply asking people to confirm by clicking the email that was sent to the email under that particular domain? (provided that website does not give out its users email addresses like gmail etc)
Because it is the most direct and 100% bulletproof way to find out if the guy has the control over the site in question.
Email address "under" the domain can belong to the admin while the site is actually managed by the developer.
Also, many use anonymous registration, in which case email will be sent to the registrar address (though it will usually forward to your real address or at least notify you).
I have a GMail account doesn't mean I own the gmail.com domain. Like 'Developer Art' said, uploading a file shows that you have access to web-hosting portion of the domain.
How would they know that you are the person at that domain responsible for the website unless you modify it in some way? I have a company e-mail address - that doesn't mean I'm responsible for the company website.
I can prove that I "own" Yahoo, Hotmail, Gmail, and many others with your proposed verification technique. What's so hard about uploading a file to a server for someone doing web work?
I think the intent is, "If you own the site, please place this verification file in your site's root directory." Once the verification system sees the file there, ownership is verified. At the very least, it confirms the ability to post to a site's root folder. Not having this expectation of your users might open you up to folks doing malicious activities as someone else's site because you didn't properly verify ownership. In legal circles, we call that, "due diligence."
E-mail... you know, I keep receiving messages from banks I don't have accounts with, the British Lottery and even more from a guy in Nigeria. They look real. Now that I think about it, maybe I should forward all of their e-mails to each other. The lottery guys and the Nigerian guy can put all their money into the fake bank accounts. Spam problem solved!

Are there white lists for Yahoo, Gmail, Hotmail and AOL?

In my website (under development), the members can send messages to each other which are sent directly to their email, now I'm worried that some members can send spam to other members (I have a spam filter but it doesn't give 100% protection as you know), I'm worried that my domain might get blacklisted on Yahoo, Gmail, Hotmail or AOL which will cause any messages sent from my domain to end up in the spam folder, this is why I want to add the domain of my website to their whitelists (if they exist).
P.S. I don't want to use private messages that members check on the site and I have my reason for this.
Thanks
Your email might not be considered "bulk" because it sounds like it's one->one as opposed to one->many, but these bulk mail help resources might still be helpful:
Yahoo! Mail Postmaster Help
GMail Bulk Sender Guidelines
Windows Live Hotmail Postmaster Services
AOL Postmaster Website
As Bevan mentioned, your task will be an ongoing one to keep your site clean on various services.
Not sure if you're already considering this, but you can send the email "on behalf of" the requesting user (i.e., set the from and reply-to fields to the user who is sending the message).
While there may be whitelists used by those sites, I suspect that they only contribute to whatever scoring system is in use - being on the list won't be sufficient in itself.
The overall controlling factor will be the "reputation" of your site - you need to work to ensure that reputation stays sound.
Unfortunately for your workload, I think this will be an ongoing task, not a one-off.

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