# Configure mail server for deployment alerts | OS Deployer

**Last Updated On**: 17 Apr 2026  
**5 minutes read**

You can receive email notifications for events such as patch deployments and configuration changes. To enable email notifications, you must first configure the mail server. Mail Server Settings can be configured using:

- OAuth Authentication
- Basic Authentication

## OAuth Authentication

OAuth is a secure authorization protocol that uses web tokens instead of passwords to grant delegated access to protected resources. It enables secure mail communication from the Central Server without exposing personal credentials.

### How to Configure OAuth Authentication?

1. Navigate to **Admin > Mail Server Settings** under Server Settings.
2. Select **OAuth** under authentication type.
3. Specify the mail server name and port.
4. Provide the sender’s name, sender’s email address, and a test mail address.
5. Choose the email type. (SMTPS is recommended for encrypted communication.)
6. Enable **TLS** if required.
7. Obtain the following credentials from the authorization server using the Redirect URL:
   - **Client ID**
   - **Client Secret**
   - **Authorize URL**
   - **Access Token URL**
   - **Scope**
8. Connect to the authorization server using a proxy if needed.
9. Click **Save**. A user consent window for the mail server will appear.
10. Enter login credentials and grant the required permissions.
11. OAuth authentication is now successfully configured.

![Mail Server Settings in Central Server](https://cdn.manageengine.com/sites/meweb/images/os-deployer/help/server/mail-server-oauth.webp)

### Frequently Asked Questions

- **Why should I switch to OAuth2.0?**  
  Google and Microsoft are deprecating basic authentication for mail servers by May 30, 2022, and October 1, 2022, respectively. It is recommended to switch to OAuth authentication.

- **Which mail servers support OAuth?**  
  OAuth authentication is tested with [Microsoft Outlook](https://www.manageengine.com/products/desktop-central/help/server/configure-O365-mail-server-settings.html) (Office365) and [Gmail](https://www.manageengine.com/products/desktop-central/help/server/configure-mail-server-using-gmail.html) (Gsuite).

- **Can I configure OAuth for an existing mail account?**  
  Yes, OAuth authentication can be configured for an existing mail account.

- **What is a Redirect URL, and where should I configure it?**  
  A Redirect URL (Reply URL) is where the Authorization Server sends response data. Copy and paste the Redirect URL into the application details in the Authorization Server settings.

- **Why do I get an error stating "Redirect URL invalid/mismatch" when saving settings?**  
  Ensure that the Redirect URL is added to the authorization server’s list of allowed Redirect URLs and that the settings are saved correctly.

- **What happens when my access token expires?**  
  When the access token expires, a new token is automatically generated using the refresh token.

## Basic Authentication

1. Navigate to **Admin > Mail Server Settings** under Server Settings.
2. Specify the mail server name and port.
3. Provide the sender’s name, email address, and a test mail address.
4. Choose an email type (SMTP or SMTPS).
5. Enable **TLS** if required.
6. If authentication is required, select **Requires Authentication** and enter the username and password.
7. Click **Save** to apply the mail server settings.