Configuring Junk Email Settings in Outlook

Summary

This guide helps you troubleshoot and resolve: Configuring Junk Email Settings in Outlook. Follow the steps below to fix the issue.

Common Causes

Types of Junk Filters

1. Low (Default)

Filters the most obvious junk email. Recommended for most users as it rarely catches legitimate mail.

2. High

Filters many suspected junk emails. Use this if you receive a large volume of spam, but be aware it might catch legitimate emails.

3. Safe Lists Only

The most aggressive setting. Only email from people in your Safe Senders List, Safe Recipients List, and contacts will be delivered. All other email goes to Junk.

4. No Automatic Filtering

Turns off the junk filter (but still blocks emails sent to your Blocked Senders list).

Step-by-Step Configuration

These instructions apply to the Outlook desktop client for Microsoft 365/Office 365. Junk email settings in Outlook on the web are managed differently through the web browser interface.

1. Changing the Junk Email Filter Level

1. Open Outlook desktop and go to the Home tab.
2. Click Junk > Junk E-mail Options…
3. Select the Options tab.
4. Choose your desired filter level:
   • Low: (Default)
   • High: (Use with caution)
   • Safe Lists Only: (Very restrictive)
   • No Automatic Filtering: (Disables filters based on content)
5. Click Apply and then OK.

2. Managing Safe Senders (Whitelist)

Use this to ensure emails from specific people or domains are never blocked.

1. Go to Home > Junk > Junk E-mail Options…
2. Click the Safe Senders tab.
3. Click Add… and type the email address (e.g., [email protected]) or domain (e.g., @example.com).
4. Click OK.

3. Managing Blocked Senders (Blacklist)

Use this to block specific people or domains.

1. Go to Home > Junk > Junk E-mail Options…
2. Click the Blocked Senders tab.
3. Click Add… and type the email address or domain you want to block.
4. Click OK.

4. Safe Recipients

If you are on a mailing list (e.g., [email protected]), adding it here prevents it from going to Junk when “Safe Lists Only” is enabled.

1. Go to Home > Junk > Junk E-mail Options…
2. Click the Safe Recipients tab.
3. Add the email address or distribution list.
4. Click OK.

5. Reviewing and Releasing Junk Items

The Junk Email folder is emptied automatically after 30 days (default).

Business practice: Check your Junk Email folder at least once a week for legitimate business messages that may have been caught by mistake.

1. Open the Junk Email folder.
2. If you find a legitimate email, right-click it and select Junk > Not Junk.
3. Check “Always trust email from [sender]” if you want to add them to Safe Senders automatically.
4. The email will move back to your Inbox.

6. Blocked Senders and Domains Sync

Outlook (Exchange/Office 365) usually syncs your Safe/Blocked lists with the server, meaning you won’t see spam even before you download it to your device (server-side filtering).

Best Practices

• Review the Junk Email folder weekly: False positives happen, and legitimate business emails can be caught by filters.
• Don’t click “Unsubscribe” on obvious spam: This confirms your email address is active, often leading to more spam. Use the Block Sender feature instead.
• Use “High” filter cautiously: It can be very aggressive. Use “Low” and manually block persistent offenders.
• Add new clients and suppliers to Safe Senders promptly: This minimises the risk of their emails being marked as junk.

Junk Email vs Phishing

Junk email is typically unwanted commercial mail or spam. Phishing is a malicious attempt to trick you into revealing passwords, financial details, or other sensitive information.

If you suspect an email is phishing:

• Do not click any links or open attachments.
• Use the Report Message add-in in Outlook to report it as phishing.
• If the add-in is not available, forward the email to your internal IT team or Open a Ticket.
• Delete the email from your Inbox and Junk Email folder.

Troubleshooting

Legitimate emails from new external contacts are blocked

• Check the Junk Email folder for the missing message.
• If found, right-click the email > Junk > Not Junk and select “Always trust email from [sender].”
• Add the sender’s email address or domain to your Safe Senders list.
• Ask the sender to check if their domain is listed on any public spam blocklists.

Safe or Blocked Senders list is not syncing with the server

• Ensure you are using Outlook desktop connected to Microsoft 365/Exchange Online.
• Run a manual Send/Receive to force synchronisation.
• Restart Outlook and check if the lists appear correctly.
• Verify that your mailbox is online and not in Cached Exchange Mode with synchronisation issues.
• If lists still do not sync, Open a Ticket for server-side investigation.

Junk button missing

Ensure you are on the Home tab. The Junk button is located in the “Delete” group.

Emails still going to Junk despite Safe Senders

• Check if “Also trust email from my Contacts” is unchecked.
• Confirm the email address is spelled perfectly in your Safe Senders list.
• If you recently added a domain to Safe Senders, wait for the server to sync or force a Send/Receive.
• Remember that Exchange Online Protection may apply additional filtering at the server level.
• For broader delivery issues, see Email not sending or receiving and Email delivery failed (NDR).

Junk folder is empty

Check your “Deleted Items” folder, or ensure the filter level isn’t set to “No Automatic Filtering.”

When to Seek Further Assistance

If you are receiving a massive amount of spam (flooding your Inbox or Junk folder) that makes Outlook unusable, Open a Ticket. IT may need to implement server-side anti-spam rules for your organisation (using Microsoft Defender for Office 365 or similar tools).

Still Having Issues?