How to set up Feishu's free SMTP service for your Discourse community

Installation Hosting
1

I was asked how to use an SMTP mail server, so I thought I’d share this recommendation for beginners. No ads, just helpful information!

Feishu (Lark) is a Chinese company that provides enterprises with a one-stop solution for workflow and work platforms. However, anyone can create an account and use its free services. Feishu offers SMTP services to free users, with a daily sending limit of 450 emails, amounting to nearly 15,000 free emails per month.

For a growing Discourse community administrator, this is incredibly valuable. You can use the free SMTP service provided by Feishu to set up your Discourse community, especially suitable for small and medium-sized Discourse communities with less than 150 active users.

Setting Up Feishu Mailbox

First, you need to register an enterprise account and log in. Note that the enterprise account information does not need to be for a real existing company; you can fill it in arbitrarily.

Part One: Enable Email Service

  1. Access the Admin Console:

A screenshot of the Lark website's admin console details for "starorion" with an option to become a Lark Ambassador, alongside a range of application icons and features like Messenger, Base, Docs, and more. (由 AI 生成标题)
A screenshot of the Lark website's admin console details for "starorion" with an option to become a Lark Ambassador, alongside a range of application icons and features like Messenger, Base, Docs, and more. (由 AI 生成标题)2444×1112 280 KB

  1. Navigate to Mail Settings:

    Click on Product Settings at the top.

The image displays the Lark Admin interface for the "star origin" organization, showcasing the Product Settings menu and various business tool options available within the platform. (由 AI 生成标题)
The image displays the Lark Admin interface for the "star origin" organization, showcasing the Product Settings menu and various business tool options available within the platform. (由 AI 生成标题)1920×855 84.3 KB

Select Mail, then click Add Domain.

This image shows a domain management interface with two domains listed, one marked as setup incomplete and the other enabled, and highlights the "Add new domain" button in the top right corner. (由 AI 生成标题)
This image shows a domain management interface with two domains listed, one marked as setup incomplete and the other enabled, and highlights the "Add new domain" button in the top right corner. (由 AI 生成标题)2434×1054 142 KB

  1. Enter Your Domain:

    • In the popup window, enter your domain name.
    • Click the Submit button.

  2. Choose “Enable New Mailbox Service”:

    • Select the option to enable a new mailbox service.

  3. Configure DNS Records:

    • Follow the instructions to configure the DNS records for your domain.
    • Go to your domain management (e.g., Cloudflare).
    • Add the necessary DNS records displayed by Feishu.

The image is a screenshot of a domain management interface, displaying TTL records for configuring DNS settings for a Lark Mail account. (由 AI 生成标题)
The image is a screenshot of a domain management interface, displaying TTL records for configuring DNS settings for a Lark Mail account. (由 AI 生成标题)2332×1504 259 KB

  1. Verify DNS Records:

    • Click the Verify Now button on the Feishu settings page.
      • If verification fails, double-check the records and wait a moment.
    • After verification is successful, click Next.

  2. Configure Mail Entry and Address:

    • Click the Configure Now button.
    • In the popup window, click Add (usually a red button or link to add a mailbox).

  3. Assign Mailboxes to Members:

    • In the member details window, find the corporate mailbox field.
    • Enter the mailbox address for the corporate member, then save.

  4. Complete Setup:

    • Return to the “Configure Mail Entry and Corporate Mailbox Address” page.
    • Click Finish to complete the setup.

Part Two: Configure a Public Mailbox for SMTP

  1. Access Public Mailbox Settings:

    • In the Feishu Admin Console, navigate to Product Settings → Mail → Public Mailbox.

This image shows a screenshot of the Lark Admin interface, specifically focusing on the Mail section where a user is dragging their cursor over to the "Create" button within the Public Mailbox. (由 AI 生成标题)
This image shows a screenshot of the Lark Admin interface, specifically focusing on the Mail section where a user is dragging their cursor over to the "Create" button within the Public Mailbox. (由 AI 生成标题)2926×1532 278 KB

  1. Create a New Public Mailbox:

    • Click Create Public Mailbox.

  2. Configure the Public Mailbox:

    • Enter the required Name and Address.
    • Enable IMAP/SMTP Services.
    • Click Create.

  3. View IMAP/SMTP Settings:

    • After creating the mailbox, find it in the list and click Edit.
      • Note down the provided IMAP/SMTP configuration information.

The image shows a public mailbox settings page with options for configuring IMAP/SMTP services, including addresses, ports, and sending restrictions. (由 AI 生成标题)
The image shows a public mailbox settings page with options for configuring IMAP/SMTP services, including addresses, ports, and sending restrictions. (由 AI 生成标题)2356×1362 186 KB

Configure the SMTP information into your Discourse server, and you’ll have a free SMTP sending service with 450 emails per day and 15,000 emails per month!

3 Likes
2

Do you need to setup more than one domain email account? When I click on public there is no option to create/add new public mailbox.

This service though is quite awesome from what I have absorbed so far.

:clinking_beer_mugs: :smiling_face_with_sunglasses: :+1: :sparkles:

3

Perhaps you need to add your domain first? If you require setting up multiple domain email addresses, simply click the domain management button on the left to add a domain.

4

I followed all steps prior. Domain added with DNS records added.

Email send & receive works. Just when I click on Public Mailbox. It just is blank.

My bad using mobile it has the box much lower on main page for initial create. Thanks.

5

To enhance the credibility of emails sent from your domain, you must also add the DKIM DNS record here.

The image shows part of the Mail app on macOS, specifically highlighting the "DKIM Authentication" feature under the "Security and Anti-spam" section. (由 AI 生成标题)
The image shows part of the Mail app on macOS, specifically highlighting the "DKIM Authentication" feature under the "Security and Anti-spam" section. (由 AI 生成标题)1284×1148 92.1 KB

1 Like
6

Thanks for the pro tip. Really appreciate your help.

1 Like
7

With the SMTP username. Do I use the public mailbox username? Or the email address that I signed up with? There is an authentication error.

8

use the public mailbox username

1 Like
9

Okay I am getting an authentication error with discourse doctor in the email test.

I am able to send and receive emails on the private email address.

I will recheck SMTP password just in case.

10

Just wondering to eliminate the double reply. Do I need to rename “info@nsfirehub.ca” to “noreply@community.nsfirehub.ca” and blankout discourse’s noreply@domqin ?

The image is a screenshot of an email notification from Nova Scotia Firehub with the subject "Greetings!" and is signed with the date and time in red. (Captioned by AI)
The image is a screenshot of an email notification from Nova Scotia Firehub with the subject "Greetings!" and is signed with the date and time in red. (Captioned by AI)863×1173 120 KB

So it only has “From” & “To” without the extra “Reply to”

11

I am not entirely clear on how this issue arose, so I shall provide you with the SMTP configuration details from my app.yml file for your reference:

# WARNING the char '#' in SMTP password can cause problems!
  DISCOURSE_SMTP_ADDRESS: smtp.larksuite.com  #The SMTP server address
  DISCOURSE_SMTP_PORT: 587  
  DISCOURSE_SMTP_USER_NAME: system@starorigin.net   #Default Sending Email Address 
  DISCOURSE_SMTP_PASSWORD: abcdef   #The default SMTP password must be entered accurately.
  DISCOURSE_SMTP_ENABLE_START_TLS: true          
  #DISCOURSE_SMTP_DOMAIN: discourse.example.com    # (required by some providers)
  DISCOURSE_NOTIFICATION_EMAIL: system@starorigin.net    # (The default notification email address)
1 Like
12

Okay thanks. I need to rename the public mailbox user to match the site’s noreply.

This should solve it. Thanks for sharing the solution.

1 Like
13

Has Lark restricted sending emails? I tested it and it’s not sending.

14

No, apparently not. The problem is likely still with your settings.

Sent via Discourse Meta notifications@meta.discoursemail.com Sunday, November 16, 2025, 1:15 PM

15

2025-11-16_16-26-35

Following your method, all sent emails were returned.

16

You can send normally using Lark’s official software or the email service on the official website. However, you cannot send through third parties.

17

It has to do with the content and quantity of the emails you sent.
Feishu’s SMTP has too small a daily quota, so I have switched to a commercial Oracle SMTP email push.

Sent via Discourse Meta notifications@meta.discoursemail.com on Sunday, November 16, 2025 at 4:37 PM:

18

Thank you very much for your reply. I am a small forum and do not need a business email.

19

A business email does not mean it’s paid.
Lark has many problems, the biggest problem is that it doesn’t go to certain mailboxes, like the one you are encountering now. I use Oracle SMTP for 100,000 emails per month at a cost of 80 RMB. Most of the time, I only use 10,000 emails per month, which is 8 RMB. If you are unwilling to spend money, then you should use free services that have problems.

Sent via Discourse Meta notifications@meta.discoursemail.com on Sunday, November 16, 2025 at 16:41: