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Managing Spam and Junk E-mail in Office 365

Refer to the information below for information about spam and junk mail filtering in Office 365.

How to Report Spam

Please use the steps below to report spam to ACNS so that it can sent to Microsoft for future inclusion in spam filtering definitions:

Messages automatically routed to Junk were successfully processed and need not be reported.

  1. Click "New Email" in Outlook to compose a new message. Address the e-mail to and enter a subject (ex: "Report as Spam")
  2. Find the suspect e-mail message(s) in your mailbox to be added as an attachment in Outlook.
  3. Drag and drop the spam e-mail from your Inbox into the new e-mail (from step 1) so that it is included as an attachment.
  4. Send the e-mail.

How Office 365 handles SPAM:

"High confidence spam," which is spam that is marked as very high probability as spam, is automatically quarantined and not delivered to user mailboxes. All other e-mail noted as possible spam is delivered to a user's Junk Email folder in Office 365. Users will no longer receive End User Digest e-mails alerting them of e-mail marked as possible spam and should check the Junk Email folder for e-mails they were expecting to receive but did not.

User's can use the options below to add safe senders and manage junk e-mail settings in Office 365. A user's safe sender list takes precedence over e-mail that would otherwise be marked as High Confidence Spam.

Blocked Attachments In Office 365

Exchange Online Protection is configured to block attachments with executable content as well as certain file types, including the following:

  • b64
  • bat
  • bhx
  • cmd
  • cpl
  • dll
  • exe
  • hqx
  • mim
  • pif
  • ps1
  • scr
  • shs
  • uu
  • vbe
  • vbs
  • wsh
  • xxe