Handling cases of sending emails via outbound SMTP (TCP25 port)

Blocking Status Explanation:

Becausetcp 25 outbound port is blocked by default, the function in websites/applications that requests externalsmtp 25 port for outbound email sending fails. Error messages include: failed to connect to the remote SMTP server, unable to telnet to the remote server's port 25, etc.

Solution:

I. The website program connects to a mail server on a non-25 port to send emails.

  1. Use a non-25 port. Use an SSL connection. For example, if using QQ Mail, enter ssl://smtp.qq.com for the smtp server and 465 for the port.

  2. Use other mapped ports. For example, some mail servers support mapping port 25 to port 80. 

 II. If it is difficult to modify the program to use a non-25 port, or you need to use the cloud host itself to provide email services:

  1. Submit an unblocking request.

  Note: Before confirming the unblocking request, you must abide by the following commitment:  

  "I promise not to use your company's servers and network to send spam. Once discovered, your company has the right to unconditionally and permanently block port 25, or permanently shut down the cloud host. I have no objection to this and hereby make this promise."

Specific steps:

1. Log in and enter the ticket submission panel page, select“Cloud Server”-->“Other Settings”-->“Apply to open server25 port (permission to send outgoing emails)”

2. Fill in the relevant host information and fill the commitment content into the “Problem Description” field, then click Submit. We will review and process it as soon as possible.