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English Our life, work, and communication are closely tied to the internet. Every user has an email address through which they need to transmit important information. Sometimes, emails don’t reach the recipient, and we need to figure out why.
There is often a need to check suspicious IP addresses that send spam and may be hiding fake bots and hackers. In this article, we will examine in detail the purpose of IP checking, email delivery criteria, reasons for getting blacklisted, and the principle of how the checking service works.
Why check if an IP is in spam databases
If your IP has been added to a spam database, email services will reject you with spam filters, even if you’re a legitimate user who has never sent spam. The reasons for this are simple:
- there’s a chance you got an IP that has been flagged for spam;
- a reader decided that your mailing list is not needed.
We can say with certainty that sooner or later any IP will end up on a blacklist. To check if you specifically have been flagged in one of the 220 largest global spam lists, or if you need to check a suspicious protocol yourself, use the proxy checker service.
Criteria for email delivery to the recipient
So, when we start sending information, we use the IP of our internet provider. If we’re sending through a special service, their protocol is used. And it’s the IP that can derail even the most impressive advertising campaign that took months to develop. Let’s understand why.
After sending, the email passes through spam filters that decide whether the email will reach the recipient. The spam filters focus on the sender’s reputation and the message content. That’s why, remember, the cleaner the IP, the higher the rating, and the more likely the sent email will end up in the inbox rather than blacklists. If the rating is high, the spam filter doesn’t even bother to ‘read’ the emails, it simply approves the sending.
What affects IP reputation
So, the main reasons for an IP getting blacklisted are:
- number of mailings from one server;
- many complaints and bans on the sender’s mailings;
- intentional spam sending;
- violation of unwritten rules of internet behavior;
- if the email contains links to domains that are already blacklisted;
- incorrectly formatted text from the spam filter’s perspective.
It sometimes happens that you’re clean and there’s nothing to fault, but your emails still end up in the spam folder. In this case, there’s a possibility that you’ve been assigned a ‘bad’ IP or the server has received an IP from a blacklist. This often occurs if you use virtual mailing services rather than professional ones that use dedicated IPs. We recommend using only professional mailing services.
How the proxy checker works
So, we already know that the IP address checking service is created to quickly obtain information about the protocol. The working principle is as follows:
- you need to enter the IP for checking;
- then you need to click the ‘check’ button.
In a couple of seconds, you get the result in the form of a list of DNSBL networks from several databases or a ‘yes’ or ‘no’ answer. That’s all. Simple, fast, informative.
