Your Microsoft 365 account may be blocked from sending emails in the following cases:
- If you try to send more than 1000 emails per hour to ULB addresses ("ulb.be")
- If you try to send more than 1000 emails per hour outside ULB addresses
- If you try to send more than 3000 emails per day
If you send a lot of emails, be sure to stay below the limits mentioned above.
To be unblocked, make a request to Support. Contact the Support by mail : email@example.com or by phone at +32 (0)2 650 3737.
If you haven't sent massive emails recently, report it to firstname.lastname@example.org.
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