Microsoft 365 - Learn about junk email and phishing

Understanding Junk Email and Spam

Mail identified as possible junk email by campus filtering is automatically moved to the Junk Email folder. Potentially dangerous content (such as links or executable code) is disabled for your safety.

Types of Junk Email

Junk Email (Spam)

Unsolicited commercial email that can clog mailboxes with unwanted or offensive content. Most of it is blocked automatically by the email server, though some may still appear in your Junk Email folder.

Phishing

Email designed to trick you into revealing private information. Messages often look like they come from trusted sources (e.g., your bank) and may include real logos or reply addresses.

See: Learn how to recognize and report phishing

Graymail (Bulk Mail)

Newsletters, marketing pitches, and subscription emails from legitimate companies. These are not always classified as spam since many people consider them valid.

Backscatter

Bounceback messages generated when a spammer forges your email address in the “From:” line. This does not mean your account has been hacked. However, if you suspect compromise, change your password immediately.

Examples include:

• Delivery Status Notifications (failed delivery or delayed delivery)
• Auto-replies (vacation/out-of-office notices)
• Challenge/response confirmations

Spoofing

When a spammer makes it appear as if an email was sent from your address. This does not involve your actual account, only your address being misused.

See: How spammers spoof your email address

FAQ

How are messages identified as junk email?

Incoming messages are scanned by spam/anti-virus software in Office 365 and given a spam score from 1–10. Messages rated 6 or higher are placed in the Junk Email folder.

What can I do with messages in my Junk Email folder?

• Do nothing — messages are automatically deleted after 30 days.
• Manually delete them — they move to your Deleted Items folder.

• Outlook on the Web: Right-click the item in Junk and choose Mark as not junk.
• Outlook Desktop: Select the item → Junk on the ribbon → Mark as Not Junk.

What if spam lands in my Inbox?

If you believe a message should have been marked as spam, report it: Microsoft 365 – Report Suspicious Message

How can I reduce spam or graymail?

1. Unsubscribe from reputable mailing lists.
2. Do not reply to spam or click unsubscribe links from questionable sources.
3. Use a “throwaway” email address for online forms and registrations.
4. Read privacy policies before sharing your email address.
5. Avoid posting your real email on public websites.
6. Create custom inbox rules for known spam patterns. See: Using Inbox Rules
7. Use block filters when appropriate. See: Filter junk email in Outlook

What else should I know?

• Manage junk email settings in Outlook on the web: Settings → Mail → Junk Email. Add safe senders or blocked senders by address or domain.
• Note: If you add hundreds of addresses to the Blocked Senders list, filtering may stop working. Keep the list small — ideally fewer than 50 entries.
• You can drag items from Junk Email to other folders as needed.
• Right-click Junk Email and choose Empty to move its contents to Deleted Items.
• If your account is forwarding email, all spam will forward as well — this can cause rejection issues.
• Consider using the Focused Inbox feature. See: Getting Started with Focused Inbox
• Learn more:
  • Junk email filter overview
  • Why emails go to spam
  • Avoiding spam filters