My emails are going to recipients spam folders

Question

Every time i send an email it is apparently going to people's spam folders. I was told this may be due to a malicious script that injected changes to your Outlook settings. How can i get this rectified so that people are receiving my emails direct to their inbox.

Answer 1

Are you using outlook.com or hotmail.com email address?

Can you use the instruction here, change the email to plain text or rich text format (basically avoid the html format) and see if it goes through:

https://support.microsoft.com/office/change-the-message-format-to-html-rich-text-format-or-plain-text-in-outlook-338a389d-11da-47fe-b693-cf41f792fefa

If it is still going to their spam folder, do you think you can ask one of your recipients to grab the email source/header, because it would contain information regarding why it is being classified as spam. You can run it through free email header analyzer https://mha.azurewebsites.net/ or if you want to share it here, make sure you remove all personal information first and I am happy to review it.

Answer 2

Follow these steps to get messages delivered to inboxes instead of spam and to rule out malicious configuration changes.

1. Ask recipients to mark messages as “Not junk”
   • Recipients should open one of the messages in their Junk/Spam folder and use the mail client’s Not junk / Not spam option.
   • This helps train Microsoft 365/Outlook.com filtering and improves sender reputation over time.
2. Check that recipients haven’t blocked the address or domain
   • Ask recipients to review their Blocked senders and domains list and remove the address or domain if present.
   • In Outlook on the web / Outlook.com they can do:
     1. Settings (gear icon).
     2. Mail > Junk email.
     3. Under Blocked senders and domains, remove the address or domain if listed.
3. Add the address or domain to Safe senders
   • Recipients can explicitly trust messages from this address or domain:
     1. At the top of the page, select Settings.
     2. Select Mail > Junk email.
     3. Under Safe senders and domains, select Add safe sender and enter the email address or domain.
     4. Select OK, then Save.
   • Messages from safe senders are not moved to Junk.
4. Check for malicious rules or forwarding (possible script changes)
   • Sign in to Outlook on the web / Outlook.com and review:
     • Settings → Mail → Rules: delete any rule that automatically moves, forwards, or modifies messages that was not created intentionally.
     • Settings → Mail → Forwarding: remove any unknown forwarding addresses.
   • If any suspicious rules or forwarding are found, remove them and then change the account password and ensure multi-factor authentication is enabled.
5. If sending from a custom domain or server, review sender reputation
   • If messages to Outlook.com or Microsoft 365 users are consistently going to Junk even when recipients have not blocked the sender, this may be a sender reputation issue.
   • Ensure that sending systems are not compromised and are not performing prohibited behaviors such as namespace mining (probing Outlook.com servers to validate addresses without actually sending mail). Microsoft blocks IPs that do this.
   • If email complies with Microsoft policies and guidelines and delivery problems persist, use the Outlook.com sender support form described in Sender Support in Outlook.com under Troubleshooting tips for IT admins to contact support for deliverability review.
6. Work with Microsoft 365 recipients when messages land in Junk
   • For recipients using Microsoft 365, if messages are incorrectly classified as spam, they can submit these as false positives to Microsoft for analysis, as described in External senders - Troubleshoot email sent to Microsoft 365 under My email landed in the recipient's Junk Email folder.
7. Verify no mobile device is misclassifying messages
   • If a Samsung mobile device with the default mail app is used with this mailbox, check its Spam addresses list:
     1. On the Samsung device, open the email app.
     2. Menu → Settings → General Settings.
     3. Select Spam addresses and remove any legitimate addresses or domains (for example, a corporate domain) that should not be treated as spam.

After completing these steps, continue to monitor whether new messages are still going to Junk. If they are, combine recipient-side safe sender configuration with sender-side checks (IP reputation, no malicious behavior, and, if applicable, contacting Outlook.com sender support).

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References:

• Filter junk email and spam in Outlook
• Sender Support in Outlook.com
• External senders - Troubleshoot email sent to Microsoft 365
• New email messages automatically move to the Junk folder in Microsoft Outlook