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How to Set Up Custom Domain for Sending Emails in Gmail

Configuration Instructions

In general, the configuration requires the following steps:

  1. Generate an application-specific password: An application-specific password is recommended for scenarios where a password needs to be entered. This password is separate from your own password and provides an extra layer of security. Even if it is leaked, it can be quickly contained.
  2. Configure the sending address and verify: Enter your sending address in Gmail’s system so that Gmail knows which address to use as the sender’s address. After providing the basic information, Gmail needs to verify that you are the owner of the corresponding domain. Only when you are the owner will Gmail allow you to send messages using that address.
  3. Set the corresponding domain as the default sending address (optional): Once the settings are complete, you can send messages using the corresponding email address. However, by default, Gmail still uses Gmail as the sender’s address. If desired, you can set the new domain as the default sending address.

Specific Steps

1. Generate an application-specific password

Google provides users with the ability to generate application-specific passwords. To do this, visit the application-specific password ( page and set the usage scenario for this password. This scenario is for your reference in case you need to identify the generated password in the future. You can set it based on specific usage scenarios, dates, etc.

Once the generation is complete, you will receive a 16-digit password. Copy and save this password, as we will use it during the configuration process.

2. Configure the sending email

Open Gmail’s account settings ( page (Settings - Accounts and Import - Send mail as), and click “Add another email address”.

In the pop-up window, enter the email name and the email address you want to bind, and click Next.

On the new page for configuring the server, enter as the server address and set the port to 587. In the username field, enter the prefix of your email (e.g., if your email is, enter hi here) and the application-specific password generated in the previous step. Choose “Secured connection using TLS” as the encryption method, and click Next.

After clicking Finish, the system will automatically verify if it can log in to the corresponding system. Once the verification is complete, an email will be sent to your email address, containing a verification code.

Next, enter the verification code on this page and click Verify, or click the link in the email to confirm the account.

3. Set the default sending email

After completing the binding, go back to Gmail’s account settings ( page. You will see multiple domains listed. Find the email address that you want to use as the sender’s domain and click “Make default” next to it to complete the configuration.


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