Managing personal Outlook.com account settings, security, and privacy
A direct account unblock cannot be performed here.
For an Outlook.com account that was temporarily blocked because of unusual activity or spam protection, use the Sign-in Helper to start the unblock process: Sign-in Helper
If the unblock does not work with the security code or password change flow, use the Microsoft account sign-in recovery guidance here: When you can't sign in to your Microsoft account
If the block was triggered by sending to many recipients at once, Outlook.com can temporarily restrict sending. Accepted guidance in similar cases is to wait 24 hours before trying again, then send a simple test message first and avoid sending large group messages in one batch.
If the issue is specifically that Outlook.com says the message was blocked due to spam protection, another accepted recommendation is to verify account security information is up to date and check for unusual sign-in activity.
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