E-mail Sending and Restrictions

Information about the rules and restrictions of sending e-mails from a web hosting service, through SMTP servers, and from VPS and dedicated servers.

Certain rules and restrictions are put in place for all our hosting services to prevent and suppress the sending of unsolicited email messages (spam).

It should be emphasized that these restrictions are not directed against most of our customers, who are decent and do not distribute unsolicited messages. The vast majority of them do not get affected by them at all.

Web Hosting and an SMTP Server

There are 2 ways of sending e-mails from web hosting services:

  • from a web hosting server through the mail() function in PHP
  • through e-mail software through our SMTP server

It is absolutely forbidden to perform any mass mailing on the web hosting service, regardless of whether it is requested or unsolicited. Therefore, it is not allowed to send various newsletters to subscribers. If a customer needs something like that, they need to find another tool, such as choosing our VPS or Dedicated Server.


  • max. amount of sent e-mails from a web hosting service – LowCost: 50 / day
  • max. amount of sent e-mails through the SMTP server – LowCost: 50 / day
  • max. amount of sent e-mails from a web hosting service – NoLimit: 500 / day
  • max. amount of sent e-mails through the SMTP server – NoLimit: 500 / day
  • max. size of sent e-mails with attachments: 100 MB

When trying to send e-mails bigger than the limit:

  • the mail() function in PHP returns false and the message is scrapped
  • the SMTP server will refuse the message with an error message informing the customer that they have exceeded the limit

The limitation applies to the calendar day, so the counter will be reset at midnight.

The listed limits can be increased. We assess the justification of such a request.

Furthermore, it is not possible to send unauthorized e-mails out of PHP via the SMTP protocol (it is not possible to establish a connection out over TCP port 25). To send mail via SMTP protocol from the web application, it is necessary to send it via authorized mail (ie. after login) via our mail server or third party server on port 587.

Virtual and Dedicated Servers

VPS and dedicated servers can be used for solicited mass mailing.

The terms for sending bulk messages from VPS and dedicated servers:

  • they must be requested messages, so the recipients must be aware that they have subscribed to these messages
  • messages must be sent in non-intrusive quantities
  • messages must be sent in reasonably small batches, not be sent in large quantities
  • the report must indicate the procedure for withdrawal and the sender must accept and respect the opt-out requests

For Virtual and Dedicated Servers, the customer is required to provide, upon request, information regarding mass messaging:

  • how the recipient’s e-mail addresses are obtained and how the subscription is obtained
  • what messages are being sent
  • how often the messages are sent
  • how much they are shipped (total number, upload speed)
  • how the recipients can cancel their subscription
  • any additional information as required

If the customer violates these terms or does not provide us with the required information, we may completely block or suspend the entire server from sending emails.

Why These Restrictions?

First of all, it is important to emphasize that these restrictions are not evil and are not primarily directed against our customers.

We do not do it at all because we assume that our customers are naughty and that they want to use our web hosting services to send spam. The most common causes and sources of spam are completely different and the customer is most often innocent.

Common Causes and Sources of Spam:

  • A security hole in a PHP script that allows it to be misused – for example, posting posts to a forum (then sending new posts to forum members), a bug directly in the contact form, and so on.
  • Stealing FTP account passwords (usually from a virus-infected home PC), the attacker then places a malicious PHP script on the customer’s website, which they then use to spam massively. The customer does not have to know at all.
  • A bug in the customer’s PHP script, which, for example, ‘loops’ and starts to send out e-mails unexpectedly.

Customers deliberately sending out spam is the last thing that happens and that we have to deal with.

Why, then, are these restrictions in place? Again, this is because the web hosting service is shared. Hence, hundreds of customers have their pages on one web server. If one of the sites begins (for any reason) to send messages in bulk and is subsequently blocked by an email server, everyone else from the same server will be blocked (because all sites have the same IP address).

E-mail servers over the Internet protect their users and customers by blocking the source of a suspicious number of e-mail messages from one source. This blocking can be temporary but also permanent. If they choose to permanently block all e-mails from our web hosting services, no customer will send anything to them (not even regular requested messages). Surely none of our customers want that.

Why isn’t the limit being dealt with when something happens? The solution must be preventive. It is too late once an attacker finds a loophole in your site’s security and starts exploiting it for mass spamming. Before we find out, analyze, and implement measures, an attacker could already have sent out tens of millions of messages, and by then the webserver would have been blocked in various places on the Internet.

This solution is not evil. Do not take it as a restriction directed against you. Take it as your protection against the misuse of your site for illegal activities. With this precautionary measure, we can ensure that the right solicited emails always reach your customers, friends, visitors, etc. from your site.

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