DLP Prevents Microsoft 365 Copilot from Processing External Email
A new (preview) DLP capability allows Microsoft 365 tenants to block Microsoft 365 Copilot from processing the content of external email. When set, any message coming from a domain that’s not in a tenant’s accepted domain list is blocked for Copilot for grounding, referencing, or summarization. It’s an effective way of blocking threat like prompt injections transmitted in email too, but some people might not like blocking all their external email.