Frequently Asked Questions List of FAQs

Outbound Port 25 Blocking (OP25B)

  1. What is Outbound Port25 Blocking?
  2. I connect to the Internet through SpinNet, and use the SpinNet outgoing mail server. Do any of the settings need to be changed?
  3. I connect to the Internet with SpinNet, and I would like to use a mail address from another company without changing it. Is this possible?
  4. I am using MYHOMEmail. Does this affect anything?
  5. I connect to the Internet using another provider company, and use a SpinNet mail address. Does this affect anything?
  6. What is the effect of Outbound Port25 Blocking on cell phone carriers?
  7. Please tell me what services are affected by Outbound Port25 Blocking.
  8. What is Submission Port 587?
  9. When I connect with SpinNet, will I be able to use it without changing Submission Port 587 settings?

1. What is Outbound Port25 Blocking?
This is implemented as a method to combat "Spam Mail" that started in the United States, and has recently been incorporated by Internet providers in Japan. In terms of virus mail, phising mail, etc., the method by which they are sent, whereby they are sent directly to other mail servers not through the mail server of the provider used for connecting, is a very serious security problem at present. In this way, Outbound Port25 Blocking denies the sending of mail (TCP Port 25) when the mail server of the provider used for connecting is not used.
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2. I connect to the Internet through SpinNet, and use the SpinNet outgoing mail server. Do any of the settings need to be changed?
Not needed.
For customers that use the Broadband Course (FLET'S Service, eADSL Service) through SpinNet, mail cannot be sent when an outgoing mail server of another provider is used. You must change to the SpinNet mail server.
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3. I connect to the Internet with SpinNet, and I would like to use a mail address from another company without changing it. Is this possible?
A Submission Port (Port 587) may be provided when another company's provider currently used provides Outbound Port25 Blocking. Customers should contact their provider for details.
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4. I am using MYHOMEmail. Does this affect anything?
No. You can continue to use the method you are currently using.
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5. I connect to the Internet using another provider company, and use a SpinNet mail address. Does this affect anything?
When the provider you use to connect to the Internet performs Outbound Port25 Blocking, use the Submission Port provided by SpinNet.
For the Submission Port, POP/SMTP over SSL in Software Setting Guide page.
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6. What is the effect of Outbound Port25 Blocking on cell phone carriers?
There is no effect on customers who have the SpinNet outgoing mail server set.
Mail can be sent to cell phone mail addresses.

Among spam mail senders, spam mail may be sent where directly connected to the mail server of the cell phone carrier.
Performing Outbound Port25 Blocking for cell phone carriers provides a safeguard to prevent mail from being sent via the mail server of the cell phone carrier when connecting to the Internet with SpinNet.

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7. Please tell me what services are affected by Outbound Port25 Blocking.
The following services are affected:
- SpinNet FLET'S Services (FLET'S ADSL, B FLET'S, FLET'S ISDN)
- SpinNet eADSL Service
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8. What is Submission Port 587?
For customers connecting to the Internet using providers that perform Outbound Port25 Blocking, this is a means of allowing mail to be sent using the SpinNet mail server.

We will no longer provide the submission port, so please use the "POP/SMTP over SSL Settings". (Sep 28, 2021)
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9. When I connect with SpinNet, will I be able to use it without changing Submission Port 587 settings?
It can be used.

We will no longer provide the submission port, so please use the "POP/SMTP over SSL Settings". (Sep 28, 2021)
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