If a message is incorrectly identified by your email hosting service as SPAM, it will be deposited in your Junk Email folder. To prevent this from happening to future messages from the sender:

  1. Locate the message in the Junk Email folder
  2. Right-click on it (while it is still in the Junk Email folder)
  3. Click "Junk", and then click "Not Junk". 

This will whitelist the sender's email address so future messages from them will land in your Inbox. 

To whitelist a sender for which there are no messages in your Junk Email folder:

  1. On the Home tab, click the Junk icon (it looks like a person symbol with a slashed red circle)
  2. Click "Junk E-mail Options". 
  3. On the Safe Senders tab click "Add" and enter the person's email address.
  4. Click OK twice.