Frequent disabling of my SMTP/Sendmail service by hostinger - sendmailr

I have a hosting at Hostinger and my mail id configured is being repeatedly disabled by the host informing me that spam mail is being forwarded from my id. I have changed my password number of times and activated my mail but after a few moments, it is again being disabled. Kindly guide as to how to solve the issue.

This usually happens when either system or users (recipients of the email) mark you email as spam.
So, avoid this:
Avoid sending mass emails especially to unverified list.
Install Recaptcha in all your contact forms and login forms.
Further, few smart advice would be:
Don’t write subject lines ALL IN CAPS.
Don’t make spelling mistakes.
Don’t plea with people to "Open Me!".
Don’t deceive readers with a false promise.
Don’t give away everything in your subject line.
Don’t use one word – like "Hi!" – as your subject line.
Skip the punctuation!!!
Don’t add "Re:" to your subject line to deceive readers.
Good luck!

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I am creating an email spammer, for an outstanding cause [closed]

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In Cuba, web access is extremely censored, so I created a tool that allows more than 50,000 people to browse the Internet through email. Cubans send me an email with an URL in the subject line, and I email them back with the response. Read more at https://apretaste.com.
It was working like a charm, till the communist government of Cuba started blocking my emails. My solution was rotation.
I started with Amazon SES, and I was changing the domain each time it was blocked, but Amazon adds a header to all emails, and once they blocked the header no email from SES was able to reach Cuba any more. The same happened with Mailgun and others, they all add headers.
Currently I am creating Gmail accounts and sending via SMTP, but Google blocks me for no reason and only allows to send 100 emails a day per account. Also I can only create few emails using the same IP address/phone, so I was forced to use anonymous proxies and fake Chinese phones. Now I am fighting a war on two fronts.
An email can be blocked by three parameters: IP address, domain, and email address.
It will be terrific if I can set up my own Postfix server at a VPS that auto-rotates the IP address. Even better if I can simulate "gmail.com", to avoid purchasing a new domain every day.
All the intents to create what I call "the ultimate sender" just either reach the spam folder or add unwanted headers making it too easy to block. I feel exhausted. I hit a knowledge barrier here.
I know I am crossing to the dark side, but this is for a very good cause. Thousands count on this service as their only source of unbiased news, social network and to feel part of the 21st century.
Can you please help me implementing "the ultimate sender", or pointing to another solution that I may be missing?
I have a few suggestions for you.
The first one relies on The Onion Router also known as Tor.
Since you are crossing to the dark side, why not also take a look into the darknet?
Take a look at this list of Tor email providers. If you have your own email server that can be accessed through Tor, it becomes much harder for anybody to stop people from using this service. After all, Tor was developed to offer people uncensored access to the web.
You can read about Tor in detail here, it uses Onion Routing and this is how you would set up your server to use Tor.
Here is an example how you could use it:
The steps that involve the setup, receiving an URL request and sending back the reply are as follows:
Set up an email server.
Configure your email server to use Tor.
Publish the public service name. (e.g. "duskgytldkxiuqc6.onion")
Deploy a client that takes the service name and a URL, and let it send an email with a request to your server.
The client now waits for a reply.
You send a reply and the client receives it.
You can change your service name on a regular basis, but you need to make it accessible to those who will use this service.
Having an own email server means being able to control the email header.
Here is one example how you could make use of it:
Configure your email server so that it receives and recognizes
emails which contain the requested URLs.
Before you send a reply modify the email header so that it shows a random IP address and a random sender email address including a random domain name.
Send your reply.
Sending an email that way means that you cannot be replied back to. But since your reply already contains the requested information there is no need to.
I hope this helps.
Crowd source it.
Find a way that volunteers can send some emails for you. This is the only long term approach that I can think of. A simple web interface with mail to links would be be enough to get started although there are other potential problems with this approach too.
Because you are talking about low numbers of users, you could also use crowdsourcing to create the single email address per person approach. They can create an account on a specific set of email providers and give you the credentials. This would allow the single email per user approach or could be used to rotate through a large set of email accounts to send emails.
The simplest solution is perhaps to set up a local SMTP server on your own computer. You don't even need a server per se.
https://sourceforge.net/projects/winsmtpserver/
There are many other such applications. They are usually used to test SMTP functions during local development, but there is nothing against actually sending spam through them.
I know this would be quite a large task, but how about pairing the users with one or just a few emails so they always receive an email from that email.
I'd assume people wouldn't have more than 100 queries per day, if so they could start receiving them from a backup email
I'd imagine it would look less suspicious for them to appear to be in constant contact with one unique email rather than 50,000 being in contact with one
I know this would be a huge undertaking, but I feel like it solves your issue.
Since the users are willing to receive emails form you then your shouldn't be blocked.
When you mentioned you are getting block does it mean your mail is going in spam or is getting lost in between sending and receiving or it is getting bounced back??
My suggestion would be to setup your own mail server and follow as below:
-Get approx 25 or more ip to rotate. (IP is the most imp part which is tracked and is accountable for the reputation of your mail server)
Don't start sending emails in bulk from the word go it is better to gradullay increase the email volume so that mail server reputation nicely built
keep changing the format of the email often
encourage user to add yourself to there contact list
your best part is user are willing to receive emails from you and you would reply to revived email is the USP of yours but still i will recommend you to register for FBL so that you would know which user is reporting you as spam and you can remove him from your list and never send him email again.
using best practice to send emails like dkim, SPF, dmarc are also vital.
Hope my answer was of some help to you. If you need step by step guide to step up mail server let me know.
My friend, do you remember what made Hillary Clinton lose the last elections to Trump?
It was the "mail" affair. And what was it? People discovered she shared confidential information through a non-official, non-governmental email account (i.e., she used some Gmail, Yahoo or another of a kind). Until here, nothing new with direct relation to your matters. But there is an small particularity on this history, and this can put, maybe not a solution, but maybe a light on a new path you could follow: Clinton actually never sent those emails; the email account she used had the password shared and the communication between people (Clinton-someone) occurred only using the drafts of the account.
How? One side logs in and accesses the drafts folder. There he/she reads the last message and edits it, cutting and writing new data - then save the draft message. On the next turn, the other side of the communication line logs in and do the same. And so forth, so never really sending those messages, but instead just updating the drafts (this "Hillary" method does schooled people... Dilma Rousseff, impeached ex-president of Brazil, actually did this method down there in Brazil too).
So, maybe if you could establish a pact with your user that he/she doesn't delete the account's password, you could pass those information by this method - without "really" exchanging emails. Maybe a "parent" email account (some that could reset a lost password) could be useful too.
Alternative: aren't you able to contract a regular HTTP webserver? You could rely on FTP to publish data to your user, he/she asks for it and you publish a page with that content.
Salvi, have you tried something with Telnet? OK, we are talking here about a text-only environment, but if nothing more would rest in the future, this could be better than nothing. Maybe you could implement a podcast-like, or push-like service based on it. Look what people do with it with references to your walk on the dark side...
If in Windows, open your command prompt.
Type telnet and press Enter.
Type "o" without quotes and press Enter.
Type "towel.blinkenlights.nl" without the quotes and press Enter.

Why is email activation useful? [closed]

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I just want to ask you why is email activation useful. I mean when you register on a website, many ask you to activate your account by email. Is this for preventing spam, or just for websites to be sure you entered a real email address, to send you emails in the future? If it is for spam, how is that preventing spam, cant bots access mail, or what?
EMail activation is primarily used to ensure that you're signing up with a "real" email address, and also one that you have access to (and therefore, presumably, are the legitimate "owner" of the email address).
This enables the website to be able to contact you at some later date since it now has a legitimate email address for you, the user. This can be used for password resets, or general communication etc.
EMail activation also effectively prevents you from signing up your friend/enemy even though you know their email address, unless you also have access to their email account, which is unlikely.
This is mostly used to stop one person from registering another person's email address with a site in order to generate spam from the site to the innocent victim. Most website's that employ such "email validation" will ignore sign-up requests unless they are "verified", usually by clicking a "secret" link or entering a "secret" code back on the website that is originally sent in the email message.
Many legitimate website users are sometimes distrustful of giving their "real" email address to websites for fear that they themselves will recieve spam from the website. Many times, this depends upon the user's trust of the website that they are visiting.
To this end, there are a number of services (such as Mailinator, SpamGourmet, and many others) that legitimate and non-legitimate users alike can employ to provide a "real" email address that is accessible by the user, yet also disposable and temporary to allow the user to ensure that they recieve no spam to their real email address.
This, to some degree, can defeat the effectiveness of an "email validation" system employed by a website, since the website now cannot guarantee that the user (identified by the email address) is "genuine" (i.e. it's not a "throwaway" email address). To this end, many website will prevent users from registering with an email address on a known "disposable" domain.
It verifies the supplied e-mail address and also prevents registering somebody else for an account or mail-list.
At least: If you forget your password, a password reset link can be sent to that email address.
There are many reasons
That way you can make sure password recovery can be done
You can be sure someone will not register someone else email to spam him
You will be protected from spambot
I think its for both , i.e to avoid spams and to make sure that you have entered a valid email address that you have access to
Well, I suppose the main reason is spam prevention and password retrieval, but if your users do something illegal, you might want to identify them.
It sure helps to ensure a valid email addresses but also helps to avoid bots that automatically register and then proceed to spam forums etc.
I'd say it's a mechanism to keep "one-stop users" away, as you have to enter a valid email adress which you have to be able to check to gain access to the website.

Handling typos in emails or signing up users

I have a web app at which visitors are signing up and getting a newsletter to the email they registered with.
I am using only a single email field in the signup form, since I wish to reduce the number of fields plus I figure most people (like me) copy and paste the email which mean a typo would propagate to the secondary verification field.
My problem is that a fair percentage of the signups have a typo in the email address, e.g. #yhaoo, #hotmaill, etc.
How can I effectively deal with such typos?
I was thinking of doing a simple auto-correction by using a list of misspellings for common domains, but I can't a ready-made comprehensive list for that.
When the form is posted, you can do an DNS lookup to see if there is a MX record for the domain. If there is not, you can be almost certain that it is a typo, because sending to that address would not get delivered. Then you could re-display the form with a friendly error message, asking the user to confirm that the email address is correct.
Don't auto-correct without prompting the user. It will be very hard to get right, and you might end up with confused users, that have their email address on a domain that closely resembles another domain.
I had this same question, and I just found a free javascript library at http://getmailcheck.org that I think will solve our problems:
The Javascript library and jQuery plugin that suggests a right domain when your users misspell it in an email address.
When your user types in "user#gmil.con", Mailcheck will suggest
"user#gmail.com".
Mailcheck will offer up suggestions for second and top level domains
too. For example, when a user types in "user#hotmail.cmo",
"hotmail.com" will be suggested.
Similarly, if only the second level domain is misspelled, it will be
corrected independently of the top level domain.
It is supposedly used by Dropbox, Lyft, Kickstarter, Khan Academy, and more.
First, you should first make a DNS lookup to see if there's a valid MX record for that domain (which implies the domain should exist) - if not you shouldn't accept that email.
Second, look for an http redirect from the domain to another domain. E.g. yayoo.com and yahooo.com both redirect to yahoo.com, so you may want to show a warning message "Did you mean ...#yahoo.com ?" or even automatically correct the addresses from a whitelist that you've made sure are safe to correct.
Lastly, if there's a valid MX record and no redirect, your remaining culprits will most likely be just typos that lead to hitfarms riding on typos for large providers (or innocent other services) e.g. gmial.com. For these you can resort to manually building a hash table of auto-correct suggestions (again, offering the user a "Did you mean.." step before accepting the submission.
I know that the question is old. But maybe my answer will help someone.
I'm using Mailgun API to handle typos in email addresses.

Setting up a no-reply email address with Google Apps [closed]

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I have my domain's email set up with Google Apps, and I am interested in sending automated emails (when users register, for example) with the From and/or Reply-To field being "no-reply#example.com". I have a few questions pertaining to how this is done:
Should I actually set up a user in Google Apps named "no-reply"?
If not setting up a "no-reply" user, should I log in with a real address (e.g.: "support#example.com") and send the email as being from "no-reply#example.com" instead? Or should I simply use the Reply-To email header?
If it's necessary to use the Reply-To header, is there a way to block the true From address (i.e.: the username I used to log into Google's SMTP server)?
Yes, you should setup a separate noreply address on your email server.
There are excellent reasons why you should set up a no-reply email address.
Why is it important to have a no-reply on bulk emails?
Many of the recipients of the email will try to hit 'reply' and they will have a multitude of reasons for doing so. Often, it is not sensible to have all of these going to a single representative at your company. Furthermore, many emails from bulk lists will be bounced back. You don't want to have to sift through these in order to find legitimate questions from your mail outs.
The best way to respond to questions rather than replying to bulk emails, is to have the recipients direct their questions to appropriate response emails either through their usual contact or via your company website.
What if recipients DO hit the reply button?
The email originator for the bulks should not just silently swallow the replies. Many companies do this and as a result, legitimate replies are ignored without any indication to your client or potential client and they, feeling neglected, go elsewhere for business.
The originating email account should be set up with an auto-responder explaining that the email was not processed and suggest alternative ways of contacting your company.
In gmail this can be done by setting up a Vacation responder with no last day. You can find the Vacation responder feature under the General tab of the account settings.
Avoid having extra accounts by setting up no-reply as a group that restricts users from outside your domain sending to it.
Unless you can think of a really good reason for it, I would suggest that you send your emails from support# rather than no-reply#.
The whole reason for a support# email address is to receive comments and feedback from your userbase, and if you're sending them emails why bother making it hard for them? If they can just reply to the email you'll receive way more feedback that way.
I suggest you set up a "Nickname" alias ( Manage Domain > Users > edit user > Add Nickname ). Then create a filter that sends any reply to that nickname straight to trash or spam.
Just set up a "no-reply" account. It won't hurt anything, people will still try to send stuff to it, and it will serve your purpose.
As for the latter two questions, it depends.
If you're sending these e-mails as a part of an automated script (i.e. forum registration) just use the "no-reply" accounts credentials. Log in periodically to make sure you aren't getting legit delivery errors (as opposed to the jokers that use fake e-mail addresses) or other odd behaviour.
If you're not sending these e-mails as a part of an automated script, it depends. If you also manage a support address (support#example.com, staff#example.com, etc.) you may want to send on behalf of, and use the reply-to. But this part is a little more subjective, and really depends on your setup.
I don't know if this will help or not, but IIRC, with gmail you can do something like
name+something_else_here#domain.com
Then, set up a filter so that emails with that "something_else_here" part go past the inbox to a label.
Does that help?
I think creating a user named no-reply is a bad approach. An alias or a restricted group is a much neater and functional solution IMHO. Also, google apps cost is based on user number.
A cool way to handle this would be using the vacation setting in GMail to send an automated response back on the no-reply email address. The vacation reminder would then remind users that this is an unmonitored email address.
I think the right thing to do is setup a filter that sorts your mailer-daemon messages into a special folder (Or trash if you so desire.) Or, like other comment have suggested, use a separate mail address.
noreply is good to indicate to people that this isn't an address you check, but it's not really the solution to dealing with bounce mail. In fact it's more likely your mail will end up in spam filters because your attempt at sender obfuscation will just look like spam to the receiving host.
You should create a noreply user. But use it as a spam mail (when registering unknown sites) and a mail for testing.

Guidelines for accepting email messages as input to application

A number of applications have the handy feature of allowing users to respond to notification emails from the application. The responses are slurped back into the application.
For example, if you were building a customer support system the email would likely contain some token to link the response back to the correct service ticket.
What are some guidelines, hints and tips for implementing this type of system? What are some potential pitfalls to be aware of? Hopefully those who have implemented systems like this can share their wisdom.
Some guidelines and considerations:
The address question: The best thing to do is to use the "+" extension part of an email (myaddr**+custom**#gmail.com) address. This makes it easier to route, but most of all, easier to keep track of the address routing to your system. Other techniques might use a token in the subject
Spam: Do spam processing outside the app, and have the app filter based on a header.
Queuing failed messages: Don't, for the most part. The standard email behavior is to try for up to 3 days to deliver a message. For an application email server, all this does is create giant spool files of mail you'll most likely never process. Only queue messages if the failure reasons are out of your control (e.g., server is down).
Invalid message handling: There are a multiple of ways a message can be invalid. Some are limitations of the library (it can't parse the address, even though its an RFC valid one). Others are because of broken clients (e.g., omitting quotes around certain headers). Other's might be too large, or use an unknown encoding, be missing critical headers, have multiple values where there should only be one, violate some semantic specific to your application, etc, etc, etc. Basically, where ever the Java mail API could throw an exception is an error handling case you must determine how to appropriately handle.
Error responses: Not every error deserves a response. Some are generated because of spam, and you should avoid sending messages back to those addresses. Others are from automated systems (yourself, a vacation responder, another application mail system, etc), and if you reply, it'll send you another message, repeating the cycle.
Client-specific hacks: like above, each client has little differences that'll complicate your code. Keep this in mind anytime you traverse the structure of a message.
Senders, replies, and loops: Depending on your situation, you might receive mail from some of the following sources:
Real people, maybe from external sources
Mailing lists
Yourself, or one of your own recipient addresses
Other mail servers (bounces, failures, etc)
Entity in another system (my-ldap-group#company.com, system-monitor#localhost)
An automated system
An alias to one of the above
An alias to an alias
Now, your first instinct is probably "Only accept mail from correct sources!", but that'll cause you lots of headaches down the line because people will send the damnedest things to an application mail server. I find its better to accept everything and explicitly deny the exceptions.
Debugging: Save a copy of the headers of any message you receive. This will help out tremendously anytime you have a problem.
--Edit--
I bought the book, Building Scalable Web Sites, mentioned by rossfabricant. It -does- have a good email section. A couple of important points it has are about handling email from wireless carriers and authentication of emails.
You can set the address that the email is sent from, what will be put into the To: address if someone just presses 'Reply-to'. Make that unique, and you'll be able to tell where it came from, and to where it must be directed back to.
When it comes to putting a name beside it though '"something here" ' - put something inviting to have them just reply to the mail. I've seen one major web-app, with Email capturing that has 'do not reply', which turns people off from actually sending anything to it though.
Building Scalable Web sites has a nice section on handling email. It's written by a Flickr developer.
(source: lsl.com.au)
EDIT: I misunderstood your question.
You could configure your email server to catch-all, and generate a unique reply-to address. E.g. CST-2343434#example.com.
A polling process on the server could read the inbox and parse out the relevant part from the received email, CS-2343434 could mean Customer Support ticket ID no. 2343434.
I implemented something like this using JavaMail API.
Just a thought.
The best way to achieve this will be to write a window service that acts like a mail client [pop3 or imap]. This windows service should execute a timed action triggered by a timer, which connects to the mail server and polls the server for any unread message(s) available in the email inbox. The email ID to check for is the email ID on which the users will give their input on/to. If the windows service client finds that there exists any new mail(s) then it should download and filter the email body and push further for processing based on the user input in the email. You can host the input processing in the same windows service but it is not advisable to do so. The windows service can put the inputs in a special application directory or database from where your main appication can read the user inputs received in email and process them as needed.
You will be required to develop a high performance TCP/IP client for doing so. I advise you not to use the default .Net library due to performance issues, instead use one of the best availabel open source TCP/IP implementations for .Net like XF.Server from kodart. we have used this in our applications and achieved remarkably grear results.
Hope this helps..
Bose has a pretty great system where they embed a Queue and Ticket ID into the email itself.
My company has the traditional Case # on the subject line, but when CREATING a case, require a specific character string "New Case" "Tech Support Issue" on the subject line to get through the spam filters.
If the email doesn't match the create or update semantics, the autoresponder sends an email back to the recipient demonstrating how to properly send an email, or directs them to our forums or web support site.
It helps eliminate the spam issue, and yet is still accessible to a wide technical audience that is still heavily email dependent.
Spam is going to be a bit of a concern. However since you are initiating the conversation you can use the presence of your unique identifier (I prefer to use the subject line - "Trouble ticket: Unable to log into web...[artf123456]") to filter out spam. Be sure to check the filter on occasion since some folks mangle the subject when replying.
Email is a cesspool of bad standards and broken clients. You need to be prepared to accept almost anything as input. You will need to be very forgiving about what kinds of input are tolerated. Anything easy for you to program will likely be difficult for your users to use correctly. Consider the old mailing list programs that require you to issue commands in the subject line. Only hardcore nerds can use those effectively. And some of those trouble-ticket CRM things you mentioned have bizarre requirements, such as forcing the user to reply between two specific text markers in the text. That sort of thing is confusing to people.
You'll need to deal with email clients that send you formatted text instead of plain text. Some email clients still don't handle HTML properly (cough GMail) so your replies will also need to be designed appropriately. There are various ways in which photos might be "uploaded" via email as well, especially when mobile phones are involved. You will need to implement various hacks and heuristics to deal with these situations.
It's also entirely possible that you will get email that is valid but unusable by the email parsing library you are using. Whether or not this is important enough to roll your own will be a judgement call.
Finally, others have mentioned using specific email addresses to uniquely identify a "conversation". This is probably the easiest way to do this, as the content of the mail will often not survive a round trip to a client. Be prepared, however, to get mail to old IDs from old customers who, instead of opening a new ticket somehow, reply to an old ticket. Your application will probably need some way to push emails with an old ID into a new case, either manually or automatically. For a CRM system it's very likely that a user would reply to an old email even if you already sent him a new email with a new ID in it. As for whether you should use some.email.address+some.id#yourdomain.com or just some.id#yourdomain.com, I'd go with the latter because the plus-sign confuses some email clients. Make your IDs guids or something and have some way to validate them (such as a CRC or something) and you'll get less junk. Humans should never have to type in the GUIDs, just reply to them. The downside is spam filtering: a user's computer might view such email addresses as spam, and there wouldn't be an easy way to whitelist the addresses.
Which reminds me: sending email these days is full of pitfalls. There are many anti-spam technologies which make it extremely hard for you to send email to your customers. You will need to research all of these and you need to be careful, and do some testing, to ensure that you can reach the major email providers. A website like Campaign Monitor
can help you if you are sending email.