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Email port 25 will be blocked for LTT ADSL, WiMAX, and FTTH Customers.

This is done to comply with international best practices that aim to reduce spam and prevent open mail relays as well as reduce emails sent by computer viruses.

What do you need to do?

We are asking you and other impacted customers to change your email program settings to port 465, which provides more security.

You will be unable to send an email over port 25 once it is disabled, and you will need to update your settings to port 465 in order to continue to send emails. Please click the link below for your current email software and follow the step-by-step instructions to change your settings.

• Outlook 2010 / 2013 / 2016
• Outlook 2007
• Apple OS X Mail
• Thunderbird Mail
• Android Mail
• Apple IOS (iPhone/iPad/iPod) Mail

Don't see your email software? Simply locate the preferences for your mail account in the software you currently use, and input the following settings:

• Outgoing (SMTP) Mail Server: mail.yourdomain.com
• Outbound Mail Server Port: 465
• Requires Authentication? Yes
• Security type: SSL/TLS (Accept all certificates)
• Username: Your full email address
• Password: Your email password

If you use another email provider, please contact your provider for its recommended port settings.  Most email providers offer an alternative to port 25 for sending an email.

How to get help?

If you need help configuring your mail client or have additional questions please visit our Help and Support site where you can get in touch with LibyanSpider Technical Support.

Additional Information

Why is it important to have port 25 blocked?

Prior to approximately 2010, ISPs allowed their customers to configure port 25 for SMTP connections between their clients and the e-mail hosting services.

Port 25 was the original SMTP port for all e-mail traffic between client software, smartphones, tablets, laptops, web forms, contact forms, and almost every other configuration where it was necessary to establish an outbound connection to an SMTP server to send e-mail.  That was prior to the outright explosion of virus and spam traffic which literally attacked the e-mail industry a few years back.

Today, more and more ISPs (Internet service providers) have blocked access to SMTP port 25 for sending mail across their networks as a tool to help curb viruses and spam.  The ISPs literally monitor the port numbers to see how they are being used and, if you have configured your Outlook, Android, Apple, or any other device to originate email traffic, they will drop the connection.

To prevent your users and customers from being blocked by the non-availability of SMTP port 25, all user accounts should always be configured to connect via the SMTP alternate ports 465 or 587.