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MC1224565 — Trust DigiCert Global Root G2 certificate authority to avoid Exchange Online email disruption

MC1224565Exchange OnlineplanForChangeUpdated: 16 March 2026

To avoid Exchange Online email disruption by March 23, 2026, organizations must trust the updated DigiCert Global Root G2 certificate and intermediates, especially if they disable Windows CTL updates or use custom/older runtimes. Failure to update may cause mail flow issues.

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Applies to: Exchange Online
Source: mc.merill.net — data via Merill Fernando's open archive (MIT).