Cannot send emails using Mozilla Thunderbird

The most common reasons not to be able to send emails are:

* Incorrect Thunderbird settings;
* Blocked port 25 by the Internet Service provider.

To resolve the problem you should try to:

1. Make sure you are using the correct Thunderbird settings:

* Incoming mail server (POP3/IMAP server):
* Outgoing mail server (SMTP server):
* Username: the full e-mail address like
* SMTP authentication must be enabled for the login to be successful.

A common mistake is to leave "My SMTP server requires authentication checkbox" unchecked. This option should be always enabled, since SiteGround servers require such authentication.

2. Try using the alternative TCP port 2525 for the SMTP server. For more information you can check our Thunderbird tutorial.

If you are having problems with your email, you may contact your host for assistance. SiteGround provides the best email hosting and we will assist you with any email issues you may have.

Setting up your email is easy when you have the right host by your side. If you need a reliable partner to help you resolve email issues and provide expert support, check out our email hosting services.


  1. Reply September 9, 2015 / 21:34 JuniorSiteGround Team

    I am experiencing problems with sending emails. Some contacts are receiving my emails and others are not.
    I am still receiving emails but cannot send or reply to certain contacts.

    • Reply September 10, 2015 / 07:45 Hristo PandjarovSiteGround Team

      I would recommend that you open a ticket in your Help Desk!

  2. Reply January 10, 2016 / 22:34 NitiSiteGround Team

    It is Thunderbird who's blocking all the emails, not the service provider. When I go to the service provider's webmail, I can send and receive emails just fine. Thunderbird is blocking my emails everytime I'm not at my home. That means, in every airport, library, or store... I cannot get emails or send emails through Thunderbird. Maybe I should download outlook.

    • Reply January 11, 2016 / 08:04 Hristo PandjarovSiteGround Team

      Maybe your email account is not configured properly. Are you getting any error message?

  3. Reply June 5, 2016 / 01:58 Thomas CzimethSiteGround Team

    No. I do not get any error message. All other part seems correctly filled.

    • Reply June 6, 2016 / 06:02 Hristo PandjarovSiteGround Team

      Please, post a ticket in your Help Desk so we can further investigate your case.

  4. Reply June 25, 2016 / 12:50 sujitSiteGround Team

    my thunderbird cant send email but my thunderbird setting is right then why thunderbird not sending my mail ???

    • Reply June 27, 2016 / 12:36 Marina YordanovaSiteGround Team

      Please post a ticket with more details (error messages you get) in your SiteGround Help Desk. Our tech team will be glad to assist you further.

  5. Reply August 11, 2016 / 07:28 Gaye WilsonSiteGround Team

    How does one post a ticket? I have the exact same problem.

    • Reply August 11, 2016 / 10:40 escalationsSiteGround Team

      Login to your SiteGround user area and post a ticket via the Help Desk available under the Support tab in your general navigation.

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