Port 25 is blocked

[kaukab]

Hi,

I  have created mail server and setup everything that it need but due to unknown reasons port 25 is blocked .

Due to port block my mail server cannot receive any emails from out side.

Can anyone from Comcast help me by unblocking the por t 25 and let me know the reason that why it was blocked and how what can i do to prevent it from blocking agin.

Thanks

[CC-Michelle1]

Thanks for reaching out regarding the blocked ports.On port 25

Inbound and outbound, is not blocked by default.

We may apply a sending block, which will prevent email programs or clients (e.g., Outlook Express) from sending email.

An unsecured port that can be used to send spam.

Customers may be advised by our Security Assurance team to switch their modem connection to a secured port that requires authentication (such as port 587). You can find more information about the ports that we block through the following link:

 https://business.comcast.com/help-and-support/internet/ports-blocked-on-comcast-network/

[kaukab]

Hi,

I think i need to explain my situation here.

We are using Comcast business plan with 5 Static ip's.

We have recently created MAIL SERVER for our office use and assigned one of the static ip from 5 ip's pool. Our server can send email without any issue but we found out that our mail server CAN NOT RECEVIE emails from any of the mail servers (Gmail, Yahoo etc.).

When we tested ports that are needed for our mail server, we found out that port 25 is blocked and due to the blockage, our mail server CAN NOT RECEVIE emails from any of the mail servers.

As for sending mails yes, we will use 587 port but for incoming mails to our mail server we need port 25 so that our mail server can RECEIVE emails from other mail servers.

Our server is currently using the following ports.

SMTP port is 587.

POP ports are 110 & 995.

IMAP port 143.

Regards,

[CC-Michelle1]

Can you please reach out through private message with the name, address and phone number on the account? 

[kaukab]

Hi,

PM sent, please check.

Regards,

[Comcast_Claude]

My apologies, it isn't showing. Please click on my name to resent the private message. 

[kaukab]

Message sent.

[CC-Michelle1]

Thank you for supplying this information. I did check to ensure that we were not blocking port 25 on your end and we are not. If we were blocking this port there are a few things to keep in mind. The only thing that would be impacted would be outgoing mail, not your incoming mail. We would also be blocking it on all IP addresses so a change of IP address is not going to assist in resolving this issue. 

[kaukab]

How can i verify that port is either bloked or not?

The server is listing on IP of one of the static IP set, is it possible that on that particuler static ip has port block?

Please help me to resolve this issue.

[kaukab]

Can anyone from Comcast staff help me to resolve this issue?

Thanks