Problems sending emails using MochaHost"s mail server (SMTP Restrictions)

This article covers several issues that you may run into when using any of our mail servers.

In order for our clients to use any of our mail (SMTP) servers, will require an additional SMTP authentication. This helps us and the Internet community to fight spam!

For more info on how to setup your email accounts, and authentication for your incoming/outgoing email connection please, review our online tutorials.

Other issues might be coming from your actual Internet Service Provider (ISP), such as:

ISP port blocking

PORT 25 BLOCKING: The most common cause of SMTP trouble is when the Internet service provider (ISP) blocks port 25, which is the default port used to send e-mail.

This forces a customer to use their ISPs outgoing mail server only.

The ISPs that block port 25 do this for two main reasons. The main reason is to curb people from sending spam mailings from the ISPs network using a different outgoing mail server than that of the ISP. Even though the mail is being sent through a different mail server than an ISPs, the mail header information still shows the messages as originating from the ISPs domain. For obvious reasons, an ISP doesnt want to be represented in this fashion, so they block port 25 to keep people from sending out through any outgoing server but the one belonging to the ISP. Another reason some ISPs will block port 25 is to attach an advertisement at the end of each and every email that is sent out through their server. Ever get an email from someone at At the end of the message, you'll see a message that says "Try Juno for free!" This is there as a free advertisement, and there's unfortunately, no way around it because they block port 25.

How to resolve the ISP port blocking issue?

MochaHost servers allow connections to alternative port number: 2525 - which all customers can use exactly in the same way as the regular port 25. You can change the default SMTP from port 25 to 2525 on most of the email applications

You will need to refer to the documentation of the email client that you use for more information on how to specify different SMTP port for your outgoing email connection.

As an alternative you can also use your ISPs outgoing mail server (SMTP). Your ISP can provide the settings for you to send email via their SMTP server. For example: "". After doing that, you will be sending mail though your ISP's servers rather than MochaHost's server.

The following ISP's are the currently known to block port 25. Juno, NetZero, AT&T, SBC Frontier, MSN EarthLink, Verizon, AOL, MediaOne, FlashNet,, Comcast, Adelphia. Please, contact your local ISP to find out if they are enforcing any limits for your service, such as SMTP block restriction.

Firewall Blocking:

For most of our accounts (such as shared packages) we have additional security measures in place in order to protect our client's email access, and prevent spam. In certain cases (such as entering your password incorrectly too many times) you may get locked out of your email account (both incoming and outgoing) temporary. This issue will resolve by itself within 1 hour.

You can contact our Live Chat support for more info if you are being blocked out of your account, and if yes what is the reason for this block.