Emails – SMTP, POP3, IMAP


You usually set up SMTP, POP3 and IMAP in e-mail clients. For instructions on the specific settings of these clients, look for them in their documentation or in the Help community center.

In this article, you will learn:

SMTP, POP3 and IMAP Protocols

These protocols serve as communication channels between email clients and servers.

  • SMTP sends mail from the web or mail client to the server. 
  • POP3 (sometimes POP) downloads mail from the server to the client, deleting mail on the server by default.
  • IMAP copies mail from the server to the client.

Connecting to Mail Servers

If you don’t want to set up an email client, or are experiencing issues, use the online WebMail client instead.

To set up the connection, you will primarily need mail server addresses. You can find them in the Service Addresses table in the hosting service detail by following these steps:

  1. Log into the customer administration panel.
  2. In the navigation bar, select Web & Email Hosting Webhosting, WMS, WebSite, or Mailhosting.
  3. Choose the mail hosting service you want to set up.

Open Detail of:

Mailhosting service SMTP(S), IMAP(S) and POP3(S) servers

In addition to mail servers, you also need to know the login name and password for the mailbox you want to connect to.

  • Login is always the entire email address, including the domain, e.g.
  • Password can be changed according to the instructions in the article Emails – Change Mailbox Password. After the change, wait around 15 minutes before trying to log in.

Sending Mail

Using the SMTP server, you can send emails both from either a client or website.

SMTP(S) – client465, 587SSL/TLS, STARTTLS
SMTP(S) – web587TLS
SMTP port and security overview

Receiving Mail

You can choose either the POP3 or IMAP protocol to receive mail.

If your chosen method of downloading mail directly deletes emails from the server, there is no backup that we can restore for you in case of data loss!

POP3/IMAP port and security overview

Common Issues

Common issues with SMTP, POP3, and IMAP setup include:

Cannot Connect to Mailserver

Issue: We’re failing to connect to SMTP, POP or IMAP.

Cause: Most common causes include using obsolete mailserver addresses and incorrect login and passwords.

Solution: First, make sure you enter the correct server address (usually in the form, or, where X is a number), username and password.

Addresses in the form are obsolete, replace them with new ones according to this guide!

Then try different combinations of ports and security. Try to change your password and log in with a new one after 15 minutes.

If that doesn’t help either, go through the other settings of the email client (including ports and security), possibly the antivirus software and the firewall of the device you’re connecting from.

Downloading Emails on Multiple Devices

Issue: Multiple devices/clients are connected to the email (for example, computer and mobile), but only one or the other is downloading the mail.

Cause: Some email clients delete messages downloaded from the server in their basic settings.

Solution: Check that all devices leave mail on the mail server (i.e. do not use POP or have specific instructions not to delete messages). The client cannot retrieve a message from the server that was deleted by the server before it was downloaded.


Question: Can I use mail server addresses in the format smtp.domain.tld, where domain.tld is my domain name?
Answer: You can, if you first set up correct CNAME DNS records.

Question: The service detail says, that the POP3 address is, is that correct?
Answer: Yes, both POP3 and IMAP use the address

Děkujeme za zpětnou vazbu!