Custom SMTP Configuration

Important Notice

We are aware of the changes implemented by the third party Google and Yahoo email services regarding their email sender guidelines. If needed, you may read more about this process with the following link: Email sender guidelines – Google Workspace Admin Help. If you are utilizing custom SMTP, you may be impacted by this change depending on your existing custom SMTP configuration. If you encounter any changes that your internal IT department cannot resolve, please contact

Simple Mail Transfer Protocol (SMTP) is an application that is used to send, receive, and relay outgoing emails between senders and receivers. When an email is sent, it's transferred over the internet from one server to another using SMTP.

The primary reason for using custom SMTP is to use your own email address (i.e. for all of the LMS emails in order to provide a more immersive experience for your Learners. Using your own email domain will also ensure that emails from the LMS don't get blocked by spam filters and/or firewalls.

Important Notes

  • Clients using OAuth with Microsoft Exchange as their custom SMTP provider must provide authorization on the Microsoft authorization page (which will appear after saving their Absorb custom SMTP settings) for the same account specified as the 'From Email Address' in the custom SMTP Settings.
    • Note: OAuth2 authorization for Custom SMTP is now available to clients using Microsoft Exchange. 
  • When sending large groups of emails from the custom SMTP service, it is important to know that some email services such as Gmail limit the number of emails that can be sent both per minute and per day. Once that limit is reached, the email service will reject further connections from Absorb's SMTP connection. Therefore, very large groups of enrollments, user creation, or other email groups may experience dropped/missing emails even when sent from this custom SMTP. Please confirm with your email service if there are limits on your account.
  • If you have Multi-Factor Authentication (MFA) enabled on the account, then you may need to either set up an App Password for this or switch to using an SMTP relay if your Custom SMTP server does not support App Passwords. Here are helpful links with further information:
  • Absorb is not responsible for the configuration and troubleshooting of third-party SMTP services
  • Absorb does not support sending messages directly as a client's email domain through the LMS

Absorb has added a new Action Tool within Portal Settings called, Edit Custom SMTP Configuration that will prompt you to update your Custom SMTP Settings within your portal.

In addition, a new field has been created called Verify SMTP Contact.

This tool allows clients and support staff to be 100% confident that they have entered the correct custom SMTP configuration prior to sending LMS emails.


Custom SMTP Configuration


To implement Custom SMTP Settings within your portal, you will need to navigate to your Portal Settings.


Once prompted to the Edit Client page, on the right-hand menu, you will see an Action Tool called,  Edit Custom SMTP Configuration.  


After clicking on the Action Tool, at the top of the page, enable the Custom SMTP toggle


Note: To assist clients during troubleshooting and support interactions, we've added a message when custom SMTP is disabled to simply inform the user that custom SMTP is disabled so emails will be sent using Absorbs email service.


Once Custom SMTP is enabled, you will be required to input the following information and choose the System Admin contact that will receive an email with a link to verify that these settings are correct.

  • Server: SMTP Server Address, e.g.
  • From Email Address: eg.
    • In the From Email Address field, you can enter an email address that will be used as the "From" for all LMS emails delivered through custom SMTP.
  • SMTP Security: You can choose between None or TLS (Transport Layer Security) encryption
    • A Client can enable TLS if they want the additional security layer, but this is dependent on their SMTP servers.
  • Port: The associated port on the server.
  • Username: This is usually the same as the From Email Address, but may be different depending on your settings.
  • Password
  • Verify SMTP Contact
    • As the tooltip suggests, after entering a new or editing a current Custom SMTP configuration, the person and/or account listed in the Verify SMTP Contact field will be sent a verification email with a clickable link which will confirm that the custom SMTP details are correct.
    • The verification email is sent using the custom SMTP information, but until the link is clicked, the custom SMTP settings will not be used to send any other LMS email.


Fill in all required fields, and click Save.

Once the Custom SMTP configuration is completed, an email will be sent to the allocated System Admin contact specified in the Verify SMTP Contact field.

Note: In order to complete the Custom SMTP process, the allocated System Admin contact will need to click the link included in the email to activate the Custom SMTP configuration.

The Verification Email

The following information will outline the Verification Email process to ensure verification is successful. 

The Verification Email:  

  • Is not listed in the Message Templates Report
  • Can’t be sent to Instructor/Learner/Supervisor/Administrator
  • Can’t be customized
  • Does use terms to support translation
  • Subject:

“Verify Your Custom SMTP Settings”

  • Body:

“This email was delivered using your new custom SMTP settings. Please click the link below to verify that you have successfully received this email and Absorb will begin using custom SMTP settings to deliver all LMS-related emails.

<insert clickable link here>

Thank you,

Absorb Software Inc.

Note: This is a system-generated message. Please do not reply to this email.”

If the link is not clicked for some reason (the email is deleted, or for some reason the person specified is unavailable), a Resend Verification button is available. Using this button invalidates the previous link, but generates a new email with a new link that will function the same way.

    • The link redirects to the LMS so an Admin will be required to log in to complete the verification if they are not already.
    • When logged in to the LMS, upon success the Admin will see a "Your custom SMTP setting has been saved." At that point, all LMS communications will be sent using the Custom SMTP setting.




SMTP Test Tool

The SMTP Test Tool will aid you in troubleshooting email-related issues by helping identify if the unexpected behavior stems from Absorb's infrastructure or if the client-side configurations need to be investigated.

The tool is available to System Admins and Custom Roles that have been duplicated from the default Absorb LMS System Admin Role.

This tool is nested in the Admin Experience > Help & Support Menu > Test Email Settings.


Instructions: How to Use the SMTP Tool

  1. Beginning from the Admin Experience, click the Help & Support menu button.
  2. Click the Test Email Setting button. The tool modal will open (SMTP Health Check).
  3. Configure the SMTP Health Check form (see table below).

  4. When you are finished configuring the form, click the Send Test Email button.

    • This will trigger the system to create and send the test email message to the address provided.  The tool will show a success or error message, based on the test results.

    • Note: Click the Cancel button to abort the process.

Field Details
Email Address

Enter the email address you want to send the test email to. This value must match the appropriate email format.


This is a required field.

Subject Line

The Subject Line cannot be modified. The default value is: Absorb LMS Email Test.

This is a required field that is auto-populated.


The email Body is pre-populated with default messaging, which can be updated if needed.

Note: This field is plain text. No additional formatting options are available.  The maximum character limit is 2000.

This is a required field.

Troubleshooting Tips

If the tool reports Success, but no email is received...

  • Check spam folders.
  • Check settings of the email client.
  • Once successfully run (and the tool displays the success message), the LMS loses sight of the message. Absorb is unable to troubleshoot from that point onwards.
Was this article helpful?
3 out of 3 found this helpful



Article is closed for comments.