Get 6 months free hosting and free domain name with all 18 month web hosting and email plans.

Troubleshooting Email

How to send email using 3 (Three) Mobile Broadband and SMTP



This article troubleshoots e-mail not sending using 3 Mobile Broadband and shows you how to fix the issue by using SMTP over port 587. Applies to our Roaming SMTP and SMTP for iPhone services.


Email will not send using your SMTP server when connected to 3 Mobile Broadband.

Your email application such as Outlook, Windows Mail, Thunderbird, Mail or iPhone may timeout when sending or return the following error;

SMTP 554 Transact Failed – Transaction failed; Port 25 error; The connection to the server has failed- Error Number: 0×800CCC0E


3 restricts access to SMTP email on port 25.


If you’ve upgraded to Ecenica Hosting Roaming SMTP or subscribe to Ecenica Hosting SMTP for iPhone, you can configure your email application to access the SMTP server on port 587.

Changing to port 587 tells your email application to connect to our SMTP servers using a different route and bypasses Three’s restrictions.

If you use your ISP to send email then you’ll need to contact your ISP for assistance. Changing the ports may still work, but you’re best asking them first if they support SMTP over port 587.

Using port 587 but still can’t send?

If you’ve updated to port 587 or are already using port 587 and still can’t send email, please consider the following;

  • Double-check your SMTP settings.
  • Some mail apps require restarting for changes to come into affect.
  • Check your firewall is allowing access over port 587.
  • Many ISP’s limit access to their SMTP to ensure you only use it for home use. If you’re trying to use your ISP’s SMTP service and ask your ISP is they support SMTP over port 587.

My ISP only supports SMTP on port 25. What now?

Why not consider our Roaming SMTP service. Ecenica Hosting Roaming SMTP gives you a flexible, dependable and secure SMTP service that you can rely on. Use at home, work or on the move. For a low fee, you can send email from any location, computer or phone – including iPhone. See How can I order Roaming SMTP?

External links

This page is wiki editable click here to edit this page.


Web Hosting – £2.99/mo

Reliable UK web hosting. Free tech support. Trusted UK host since 2004. Free setup. Order online.

cPanel Hosting – £4.99/mo

Fast cPanel hosting with email. Choice of UK/US servers. 30-day money-back promise. Founded 2004.


Related posts:


Tags: , , , , , , , , , , , , , , , , , , ,

Share this article

If you found this article useful, please feel free to re-tweet. The Url for this post:

Leave a Reply

You must be logged in to post a comment.

Still need help?

Please login to account and submit a new support ticket.


Unless stated, this article is subject to Ecenica Hosting copyright protection. We've worked really hard to bring you this site so before you click copy & paste please take a moment to read our Copyright Notice.

Back to Top