If you use Hotmail: Check the Junk folder. If email from a sender you want to whitelist is in this folder, click Show Content to view the body of the email, then click Mark as Safe. The Sender will now be added to your list of Safe senders. Alternately, you can manually add to your Safe List by clicking Options in the upper right corner of your Hotmail screen, then in the body of the page under Junk e-mail click the link Safe and blocked senders. From there, click the link Safe senders and enter the email address you want to whitelist, then click Add to list.