Spam Filtering and Whitelisting

Spam filtering checks incoming messages for signs of bulk mail, fraud, malware, and spoofing. Filter controls may be available per mailbox or domain, depending on your account permissions.

Review spam settings

  1. Open the email or spam-filter settings for the mailbox or domain.
  2. Review the current filter sensitivity and spam handling action.
  3. Choose whether likely spam should be tagged, moved to a spam folder, or rejected, based on the options available.
  4. Check the spam folder regularly, especially after changing filter sensitivity.

The names and available controls can differ by account. If you do not see these settings, ask your mail administrator.

Allow a trusted sender

Use an allowlist only when a legitimate sender is repeatedly misclassified as spam.

  1. Confirm the sender through a trusted channel.
  2. Add the exact email address, or a domain only when you trust all senders from it, to the allowlist.
  3. Save the change and ask the sender to send a new message.
  4. Review the message headers and filter results if it is still blocked.

Allowlisting bypasses some filtering and can let forged or compromised messages through. Avoid broad entries such as a public email provider’s entire domain.

Block a sender

Add a sender address or domain to the blocklist when unwanted messages continue to arrive. Blocking a full domain may also block legitimate messages from that organization, so prefer the narrowest entry that solves the issue.

When legitimate mail is blocked

  • Check the spam folder and release the message if it is safe.
  • Ask the sender to verify their SPF, DKIM, and DMARC configuration.
  • Review the message’s spam score and headers using spam score and header analysis.
  • Add a narrow allowlist entry only if needed, then monitor the result.

Do not open unexpected attachments or follow links just because a message came from an allowlisted sender.