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Port 25 - Things to know from AT&T
Port 25 Blocked
Port 25 is blocked over AT&T internet. The reasons for this is to provide a more secure internet connection and reducing the amount of spam and viruses that come through Port 25. It is estimated that 80% of the e-mail traffic carried on the network is spam. Spammers have become increasingly sophisticated and go to great lengths to cover their tracks and send countless e-mails flooding your inbox and the internet.
Getting around the Port 25 Block
If you use port 25 to send E-mail, there are a few options to get around this block.
- Configure your mail server to use a different port. Many mail servers no longer use port 25, and it may be best to get the changes made to move away from port 25.
- Verify your E-mail address. Once you verify your third party E-mail with the AT&T mail servers, E-mail through that mailing address will be allowed to travel through the AT&T mail servers. To do so:
- Log in to your online mail.
- Select the gear icon in the upper-right corner of the page, and select Settings.
- Select Writing email.
- In the Add send-only address field, enter the email address you'd like to add.
- Select Verify. A verification message will be sent to the email address you entered.
- Select the verification link in the message to verify your account.
David, AT&T Community Specialist
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