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I am currently facing an issue sending emails from sendgrid to oulook or hotmail users:
550 5.7.1 Unfortunately, messages from [XX.XX.XX.XX] weren't sent.
Please contact your Internet service provider since part of their
network is on our block list (S3140). You can also refer your provider
to http://mail.live.com/mail/troubleshooting.aspx#errors.
Sengrid support keeps saying that it is my responsability to maintain dedicated IP reputation. The thing is that this IP was added to my account some weeks ago and I am not able to build any reputation since all emails are dropped by Microsoft. Other providers like Yahoo or Google are handling correctly our emails.
Also, checking IP in block lists, it is not listed in any of SPAM lists.
Can someone help me here?
Many thanks in advance.
Best regards,
Eduardo
From what you've shared, it sounds like you are using a dedicated IP address. The error you're seeing is due to you sending to a Microsoft owned email servers from an IP address they are unfamiliar with. Unfortunately Microsoft tends to auto-block new IPs, not just IPs with a poor sending reputation/history.
Are you sending email from new IP addresses?
IP addresses not previously used to send email typically don't have any reputation built up in our systems. As a result, emails from new IPs are more likely to experience delivery issues. Once the IP has built a reputation for not sending spam, EOP will typically allow for a better email delivery experience.
New IPs that are added for domains that are authenticated under existing SPF records typically experience the added benefit of inheriting some of the domain's sending reputation. If your domain has a good sending reputation new IPs may experience a faster ramp up time. A new IP can expect to be fully ramped within a couple of weeks or sooner depending on volume, list accuracy, and junk email complaint rates.
I recommend completing the Hotmail Blacklist Removal form. I also highly recommend this RackAid post about troubleshooting Hotmail delivery issues, which includes this gem of a pro-tip:
Usually, within 24-48 hours, you should receive notice of their decision. Typically, you receive one of two replies:
Not qualified for mitigation
We have implemented mitigation
If you receive the not qualified response, reply to the email. Ask for clarification as to why your IP did not qualify. You will usually receive a response in 24-48 hours. The response comes from a real tech who will work with you to resolve the issue.
If you IP qualifies for mitigation, you should see the Hotmail email block removed in 24 hours.
You may also want to use Microsoft's delisting portal, although I have seen the most benefit for SG users coming from using the "Hotmail" support form linked above.
Related
I have tried to have my SMTP server with exim4 for a while to send ecommerce registration and transaction confirms.
I followed all the good rules, like SPF, DKIM, DMARC, SMTP encryption. The postmaster tool by google said the IP has a good reputation and there are not spam traffic.
I reached a antispam test result of 10/10 using https://www.mail-tester.com/ or some similar tools.
But everything was not enough, my ecommerce registration messages are sent to spam by Gmail and it is the same with some other famous providers. I have understood I can't do nothing against.
Then, what is a good solution for user registration for an ecommerce? How can I reduce the messages delivered to spam folder?
I'm afraid you haven't provided enough information to identify the problem.
Hundreds of factors can contribute to deliverability outcomes; it's not as simple as setting up authentication, reverse DNS, etc. In addition, no free mail tester can accurately tell you how your deliverability will be at Gmail, Outlook, Yahoo, etc., because mail testers don't have the same data those ISPs use to make spam filtering decisions.
If you want more reliable deliverability, it's generally easiest to use a transactional email service to send email, rather than trying to run an SMTP server yourself. There are occasional exceptions to this, but because most senders will have an easier time using one of these services, it's almost always the first thing to try.
(How do email services provide better deliverability? A number of ways, but I think the biggest difference is that they can more closely manage the email sending reputation of their IP ranges. Having anti-spam systems built into the service enables them to resolve problems that much faster, compared to hosting providers which tend to have fewer tools and less data available to stop spammers, so their IP ranges' sending reputation is usually worse.)
Here is something you can try that may help.
Use a 3rd-party delivery provider (AWS SES, SendGrid, Mailgun) with a Good IP reputation. Here's a list of places you can check their IP reputation https://www.helloinbox.email/#reputation (Talos and Barracuda).
Use a subdomain to send transactional emails (email.example.com).
Let me know if that doesn't work.
Let's imagine that I have a site with some features that require email validation (eg. user registration). Of course I will validate emails using regex but once upon a time I saw SMTP validation in someone else's code. What good and bad sides has SMTP validation?
I can assume the following pros and cons:
Pros:
We can check out some email addresses for existence (not all SMTP servers allows this feature).
Cons:
Our site can be blocked.
Maybe we can use this to make webserver going down. Webserver will take domain part of email address and make request to it. We can create fake SMTP server that will receive request but will make great delay to response. Maybe if we force webserver to make dozens of such checks it will not be able to answer other clients.
Not all SMTP servers provide this capability.
Please be constructive.
"SMTP Validation" I assume refers to the SMTP VRFY command, and in this day and age you would be a fool to trust in it. It's a great feature if you're a spammer because it allows you to enumerate email addresses for a given server.
No one in their right mind will expose this command to the internet and have it respond with anything other than 252 send some mail, i'll try my best, aka "I'm only going to validate email addresses during an actual mail transaction".
The only sane use of VRFY these days is as an internal interface between a spam filtering appliance and the mail server hiding behind it.
TL;DR Don't use "SMTP Validation", it will be horribly unreliable at best.
If you want to validate that a user has entered a valid email address, then send it an email with an activation link/code.
In addition to Sammitch's answer, there are email validation services available via API that can provide SMTP validation - sometimes down to the mailbox level - for reasonable prices.
You can find these with a simple Google search, but I'm told LeadSpend and QAS (an Experian subsidiary) are among the best of the bunch.
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I'm living in Ukraine and maybe you know that we have some serious problems in our country. Ukraineans nowadays have no rights and almost everyone who trying to do something about it(fight for democratic ideals) are treated as enemy of the state. Police kidnap own people and torture them in prisons.
I'm an author of Chrome extension and this is my way to fight against tyranny. Still i'm worrying for myself and my relatives that someone could somehow find my personal information through its page in the store. And you need a credit card to register chrome extension in store(onetime $5 payment) so all my information is linked to my account in store.
So my question is next: could my personal info can be found through extension page in the store ? And maybe there is a way to hide such info..?
You should probably use a completely separate Google Account than the one you ordinarily use for uploading this extension. The webstore does show other apps created by the same author, so if you were to upload multiple extensions from the same account, and it was known who created the other extensions, that would be one way to tie it back to you. The other things that could tie an extension back to you are the contents of the extension (e.g. if you had your own personally identifying information in the HTML or JavaScript embedded in the extension code). Another way that they could attempt to unmask you is by sending an email with a virus to this account (the webstore does provide a way to contact the extension's author, I believe).
Google does comply with valid legal requests. Interestingly, Google's Transparency report doesn't seem to show any data on requests for user data from Ukraine. I doubt that, faced with a request to de-anonymize a dissident who has otherwise done nothing wrong, that Google would comply. That being said, as a political dissident, it's always better to be safe than sorry. For making the registration payment, you might want to use MaskMe or a similar masking service. You might also want to use a VPN for all of this so that all your activities (both encrypted and not) occur outside of Ukraine.
Anyway, that is a very interesting question, and I wish you the best of luck in restoring santity and democracy over in that part of the world.
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I have scenario for which I am looking for a message queue service which supports below:
Ease to Use
Very high in performance
Message once read shouldn't be available for other consumers.
Should have capability to delete the message once read.
Message once published should not get dropped.
The scenario which I have is described below:
There are many publishers.
There will be many consumers.
Queuing server and consumers residing on same machine, but publishers are residing on different machines.
Please let me know best queuing service apart from Rabbitmq and sqs satisfying above points
I would recommend Apache Kafka: http://kafka.apache.org/
If you want to know a comparison between Kafka and RabbitMQ you should read this article: http://www.quora.com/RabbitMQ/RabbitMQ-vs-Kafka-which-one-for-durable-messaging-with-good-query-features
Also, you should take a look to this: ActiveMQ or RabbitMQ or ZeroMQ or
Kafka as far I know is mainly meant for real data propagation and I think my requirement doesn't require something like kafka. I have used SQS but the only problem I have with SQS is high latency. Publisher pushed message to queue and consumer keep on polling for new message, this implementation is hitting me with very high latency. My requirement is simple as follows:
Queue service should have high availability and reliability like SQS
Latency should be very high lets say not more than 10ms. (here 10ms includes publishing and receiving the message).
Also my message size is very small say not more than 20-30 bytes.
I have thought of using redis, in which I will be pushing the messages to a list and workers will keep on popping them back to back till list becomes empty, but I have not done any benchmarking on that. So here I really need suggestion so I go in right direction.
Thanks,
For some of my system integration projects I met the MQ-tasks. Several rich costumers wants the production solutions like IBM WebSphere MQ, but I think it's too much expressive and difficult.
I found and used the simple and stable analog: e-mail server.
All integrated systems got the local e-mail boxes. Messages are e-mail, with command-code in subject and json in attachments. E-mail server listen and dispatch all queues, to recipients or to groups of them. E-mail protocols are stable and all developers know a lot of tools to work with it. Sysadmins and testers use the simple e-mail clients for testing and auditing. All e-mail servers have a logging tools.
It's best and easy solution, and I suggest it for most of integration projects.
We need to write a .Net (C#) application that monitors all mail activity through a POP, SMTP and Exchange Server (2007 and later) and essentially grab the mail for archiving into a document management system. I realise that the way to monitor each type of server would probably be different so I'd like to know what the best (most elegant and reliable) way is to achieve this.
Thanks.
Many countries have rather narrow regulations for what such a system must do and what it must not do in order to be in compliance with the law. If you are developing a product for a company in SA that wants to sell it internationally, I would suggest that need a more targeted approach.
Depending on the legal framework, your solution will have to intercept and archive all emails, or just a subset.
For instance, some countries do not allow the company to store private emails of employees, in which case the archival process needs to be configurable with rules that the employee can control.
If the intent is to archive each and every email, then the network-level approach that Jimmy Chandra suggested is better, because it is easier to deploy.
I don't think you need to worry about POP right? it is not used for sending mails (unless you need to monitor access to emails too).
Regarding Exchange, versions 2000 onwards have Journaling support (don't know about previous ones), so a mail is copied cto a mailbox as it is sent/recieved (there are several different options depending Exchange version, check it out). Then you can read that mailbox or set a rule to forward it to an external SMTP, and you app listen to it.
For other SMTP servers, it would be possible to get a similar approach by forwarding rules etc, and some might have custom support as Exchange has.