A very useful tool in the fight against spam is Outlook’s ability to define lists of e-mail addresses and domains that are always blocked or always allowed through.
A safe sender is a person, or more precisely an e-mail address, whose e-mail messages are always considered to be okay—not spam—regardless of the content. Sometimes a safe senders list is called a white list. You can create a safe senders list based on your contacts and by entering individual addresses. You can also specify entire domains as safe—for example, all messages from Microsoft.com would be considered to be safe. Here are the steps to follow:
Choose Tools Options from the main Outlook window to display the Options dialog box.
On the Preferences tab, click the Junk E-Mail button. Outlook displays the Junk E-Mail dialog box.
If necessary, click the Safe Senders tab (shown in Figure 28-2).
Figure 28-2. Defining your Safe Senders list.