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Shane 0

My emails bounce back with this response:

Diagnostic information for administrators:

Generating server: KL1PR0401MB6514.apcprd04.prod.outlook.com

"PII removed@hotmail.com" Remote server returned '554 5.7.0 < #5.7.520 smtp;550 5.7.520 Message blocked because it contains content identified as spam. AS(4810)>'

I have just opened this account to use because my old hotmail was potentially hacked as I had to verify each time I was sending an email with over 50 Bcc recipients. Now I can't even log onto that hotmail account on the browser - only in the App. Why does my new Outlook emails come up as spam?

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Sin-D 10,315 Microsoft External Staff Moderator

Hello Shane,

Thank you for posting your question in the Microsoft Q&A Forum. I understand that you are experiencing email bounce-back whenever you send emails, and I’m sorry for the inconvenience. Could you confirm whether the bounced email included any PDF attachments?

If your email contained PDF attachments, please check this article for a workaround option: Unable to attach files in Outlook.com.

Otherwise, you can try adjusting Settings (gear icon) > Search for "Compose and reply" in search box > Change Message format from Compose messages in HTML to Plain text format in your settings to see if that resolves the issue.

Regarding the email account that cannot log in, could you provide the exact message Microsoft displays when you attempt to sign in? (Please remove any personal information before sharing.) This will help me guide you more effectively.

Thank you so much. If you still need assistance, please click “Add Comment” to follow up with me.

If the answer is helpful, please click "Accept Answer" and kindly upvote it. If you have extra questions about this answer, please click "Comment".

Note: Please follow the steps in our documentation to enable e-mail notifications if you want to receive the related email notification for this thread.

Best regards.

Sin-D 10,315 Reputation points Microsoft External Staff Moderator

2025-10-12T02:29:36.0766667+00:00

Hi Shane,

I just wanted to check in and see if the steps worked for you. Additionally, I’d like to ask: Are your emails failing to send to all recipients or only to specific ones? Do they still work when you use your phone or another Outlook platform?

If yes, you can try drafting the email in the web version and then sending it from your phone or other platforms. Another option is to draft it in the web version, then open DevTools (usually by pressing F12) → click Toggle Device Emulation (located in the top-left corner of the DevTools window) or use Ctrl + Shift + M when DevTools is open and reload the page. Try using both methods as a temporary workaround if you need to send the email urgently.

Please keep me update so I can follow up on your case. If you find this helpful, I’d appreciate it if you could click Mark Answered.
Sin-D 10,315 Reputation points Microsoft External Staff Moderator

2025-10-14T06:12:49.1733333+00:00

Hi Shane,

I just wanted to check in one more time and see if the steps worked for you. If everything is set, it would be greatly appreciated if you could mark the answer as Accepted. This helps others facing similar issues and keeps things organized.

If you need any further assistance, don’t hesitate to reach out!

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