1. If junk mail is not already highlighted in brown to indicate that it’s junk, check your junk mail preferences
  2. Choose Mail > Preferences, then Click Junk Mail. Make sure “Enable junk mail filtering” and “Mark as junk mail, but leave it in my Inbox” are selected
  3. If the problem persists, click Reset in Junk Mail preferences to rest the junk mail database to its original information. Resetting the database removes everything Mail has learned from you about what is junk or not junk, so you need to help Mail identify junk mail again

How to Whitelist Sending Email Addresses in Mac OS X Mail:

  1. Select Mail | Preferences… from the menu in Mac OS X Mail.
  2. Go to the Junk Mail category.
  3. Make sure Sender of message is my Contacts (or Sender of message is in my Address Book) is checked under The following types of messages are exempt from junk mail filtering:.
  4. Optionally, check Sender of message is in my Previous Recipients as well.
  5. Close the preferences window.
  6. Add any known sender to your Mac OS X Address Book.

How to Whitelist Sending Domains in Mac OS X Mail:

  1. Select Mail | Preferences… from the menu in Mac OS X Mail.
  2. Go to the Rules category.
  3. Click Add Rule.
  4. Type a Description (such as “Whitelist: opisnet.com”).
  5. Make sure the criteria read: “If any of the following conditions are met: From Ends with.”
  6. Enter the domain name you want to whitelist after “Ends with.”
    1. To whitelist all mail from the “opisnet.com” domain for instance, type “@opisnet.com.”
    2. You can filter multiple domains with one rule. Click the plus sign next to the last condition and add another domain with the same criteria.
  7. Make the actions read: “Perform the following actions: Move Message to mailbox: Inbox.”
  8. Click OK.
  9. Make sure the rule is executed before other rules that might act on the same message for other reasons by dragging it near the top of the rules list.
    1. If you have a filter that color-codes certain messages based on keywords in the subject, for example, make sure the domain whitelist rule is above that labeling rule.
  10. Close the Rules window.
  1. In the Spam Folder, click on the email that you want to mark as not spam
  2. Click the “Not Spam” button that appears at the top and bottom of your mailbox view
  3. Unmarking a message will automatically move it in to your inbox
  1. In Mail, click the “Junk Email” folder in the Navigation Pane
  2. In the message list, click any message that you want to mark as not junk
  3. On the Home tab, in the delete group,  click on the “Junk” option then click “Not Junk” on the drop-down menu
  1. Click the “Spam” folder, where junk emails are stored
  2. Click the email that was incorrectly classified as junk mail to open it
  3. Click the “Not Spam” button in the toolbox to immediately send the email to the Inbox folder. Emails from the same sender will not be treated as junk mail anymore and will be sent to your Inbox.

If you find that some senders’ messages continue to be mislabeled as junk or spam, you can prevent this by adding their email addresses to your Contacts List or Safe Senders List.