Deny sending SMS messages on Samsung devices using Knox Service Plugin

Learn how to deny sending SMS messages on Samsung devices using managed configurations for the Knox Service Plugin app.

Requirements

• You must have a Miradore Premium or Premium+ subscription, or an active trial.
• Managed Google Play Enterprise must be configured for your Miradore site.

Configure denying sending SMS messages

The Knox Service Plugin application allows you to control incoming and outgoing SMS messages. This guide helps you to configure the Knox Service Plugin to allow incoming SMS messages while denying sending them.

For this restriction to work, Rich Communication Services (RCS) messaging must be disabled for the device to fall back to using SMS. This is because devices using the Samsung Messages or Google Messages app use the RCS protocol for messaging instead of SMS.

1. Navigate to Management > Applications and select Add > Android application.
2. Select Managed Google Play store, then select Next.
3. Search for Knox Service Plugin and select its tile from the results.
4. Click Select.
   Result: The application's page opens. The same page can be opened by navigating to Management > Applications and double-clicking the application's row in the table.
5. On the Configurations tab, click Select configuration > Add configuration.
6. Enter a name for your configuration in the text box and press Enter.
   Note: You can make the configuration default for the application by ticking the Default checkbox.
   Result: The newly created configuration is open on the Configurations tab.
7. Optional: Add the Debug Mode setting to the configuration by selecting the  icon on the right.
   Tip: Debug Mode shows policy results and errors on the device; use it only during testing and disable it before final deployment.
   
   1. In the Add managed property to application configuration wizard, select the Value checkbox.
   2. Select Add, then Close to exit the wizard.
8. Add the Device-wide policies (Selectively applicable to Fully Manage Device (DO) or Work Profile-on company owned devices (WP-C) mode as noted) setting to the configuration by selecting the icon on the right.
   
   1. Select Add in the Add managed property to application configuration wizard.
   2. Select Close to exit the wizard.
9. Expand the Device-wide policies (Selectively applicable to Fully Manage Device (DO) or Work Profile-on company owned devices (WP-C) mode as noted) setting and add the Enable device policy controls setting to the configuration by selecting the icon on the right.
   
   1. In the Add managed property to application configuration wizard, select the Value checkbox.
   2. Select Add, then Close to exit the wizard.
10. Expand the Device-wide policies (Selectively applicable to Fully Manage Device (DO) or Work Profile-on company owned devices (WP-C) mode as noted) setting and add the Call and Messaging control setting to the configuration by selecting the icon on the right.
    
    1. Select Add in the Add managed property to application configuration wizard.
    2. Select Close to exit the wizard.
11. Expand the Call and Messaging control setting and add the Enable call and messaging controls setting to the configuration by selecting the icon on the right.
    
    1. In the Add managed property to application configuration wizard, select the Value checkbox.
    2. Select Add, then Close to exit the wizard.
12. Expand the Call and Messaging control setting and add the Manage RCS messaging setting to the configuration by selecting the icon on the right.
    
    1. In the Add managed property to application configuration wizard, select the Value checkbox to disable RCS messaging.
       Result: The Value column of the Configuration table shows True.
    2. Select Add, then Close to exit the wizard.
13. Expand the Call and Messaging control setting and add the SMS Controls setting to the configuration by selecting the icon on the right.
    
    1. Select Add in the Add managed property to application configuration wizard.
    2. Select Close to exit the wizard.
14. Expand the SMS Controls setting and add the Blocklist Outgoing SMS restriction setting to the configuration by selecting the icon on the right.
    
    1. In the Add managed property to application configuration wizard, enter .* in the Value field to block sending SMS messages from all numbers associated with the device.
    2. Select Add, then Close to exit the wizard.
15. Optional: Add the Profile name(version) setting to the configuration by selecting the  icon on the right.
    Tip: The Profile name(version) setting can help with tracking and debugging during the testing of the configuration.
    1. In the Add managed property to application configuration wizard, enter a unique profile name and version in the text box, then select Add.
16. Deploy the configured application to the managed devices.
    Tip: It is recommended to deploy the configuration to a test device first. If the test is successful, remove the Debug Mode setting from the configuration before deploying it to your managed devices.

Results: Sending SMS messages from the managed device is denied. The device can still receive incoming SMS messages.