Users generally do not want to receive e-mails sent by Microsoft Viva. So how can we turn off these notifications (briefing mails)?
Sign in to the Microsoft 365 Admin Center (admin.microsoft.com)
Go to Settings>>Organization Settings menu and open “Briefing email from Microsoft Viva”. Uncheck Let people in your organization receive Briefing email option.
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The change will take effect within 24 hours and your users will not receive a daily or weekly briefing mail.