1. Make sure that Chatter is enabled in your org.
2. Open Community Workspaces orCommunity Management.
3. Under Administration, click Preferences.
4. Select Enable direct messages and save your changes.
5. In Community Builder, click the Profile Header component on the community Home page and select Include My Messages. The My Messages link appears in the user profile dropdown menu.
6. Optionally, add other components to your community pages to facilitate easy access to direct messages.Add the Messages page to your community’s navigation menu for prominent placement and easy access.Add the New Message Button component to any page you want to allow community members to create messages from.Add the Message Notification component to the community home page.
7. Add the Messages page to your community’s navigation menu for prominent placement and easy access.
8. Add the New Message Button component to any page you want to allow community members to create messages from.
9. Add the Message Notification component to the community home page.
10. Publish your community.