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Posted inExchange Online
Limiting onmicrosoft domain usage for sending emails [MC1143991]
Message ID: MC1143991 IntroductionTo improve email deliverability and reduce abuse, Microsoft is introducing outbound email throttling for default MOERA domains (e.g., contoso.onmicrosoft.com). These domains are intended for initial tenant setup and testing—not for regular email traffic. This change encourages organizations…
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