Outlook/Hotmail account can receive replies but cannot receive new emails (550 mailbox unavailable)

Question

Hello,

My Hotmail account can sign in normally and I can send emails, but I cannot receive any incoming emails.

When someone sends an email to me, they receive an error similar to:

550 5.5.0 mailbox unavailable

What I already checked:

• Account login works
• Outlook web works
• Password changed
• Security verification completed
• Account is not full (storage OK)

This issue started suddenly and looks like a server-side mailbox problem.

I believe the mailbox provisioning or backend status may be broken.

Could a Microsoft moderator please check or escalate this to the backend team?

Thank you.

Answer 1

Hello,

Make sure you do this on a computer, not on smartphone or tablet. Go to https://www.outlook.com and log in, click on the gear icon on the top right to launch the settings.

Then, on the Mail tab, go to Rules. Are there any rules set up here? If yes, delete them all.

Then check the conditional format, again, if it's there, delete it.

Then, check Forwarding and IMAP, If any items are present, delete them as well.

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If you can't find anything, go to https://account.live.com > Your info > Sign in Preferences. Make sure to check all the aliases here. If you don't recognize any there, delete it.

Then go to Security > Manage How I sign in, make sure all contact info is yours. Then scroll down on the same page, look under App Password, click on remove existing app passwords as well.

Please make sure you change your password and enable two-step verficiation.

Go to your account online, go to Devices, remove any devices you don't recognize.

Then go to Security, click on Sign out everywhere. This is meant to kill any session that's still connected. Unfortunately, this one will take 24 hours to take effect.