Outgoing Mail Submission Port (587)

Who this page is for

This page is for Asahi Net members whose Internet connection is being provided by another Internet provider that is engaged in Outbound Port 25 Blocking. The member may have problems sending their Asahi Net email and may need to to use outgoing mail submission port 587.

What is the outgoing mail submission port (587)?

As one method to combat the sending of unsolicited email, some Internet providers are using Outbound Port 25 Blocking to prevent users of other Internet providers from being able to send email through port 25.

Asahi Net members using another Internet provider for their Internet connection, and finding that the Internet provider is employing Outbound Port 25 Blocking, will not be able to send their Asahi Net email.

In this case, using the Outgoing Mail Submission Port (587) will allow Asahi Net email to be sent.

It will be necessary to change some of your settings.

Precautions and settings

  • Change the Outgoing mail server port setting in your email software to 587.
  • Use SMTP authentication settings.
    >> What is SMTP authentication?
  • Make sure the password is entered in lower case characters.
  • In these cases, there is no need for the submission port 587 setting.
    • If using an Asahi Net Internet connection service.
    • If sending of email is possible with the SMTP over SSL setting.
    • If not using an Asahi Net Outgoing mail server.
    • If the Internet provider is not using Outbound Port 25 Blocking

Compatible outgoing mail servers

Outgoing Mail
(SMTP) Server

Email software settings

For the settings required for various email software, please visit this page:
>> Email Software