In this video the instructor shows how to allow email from people you know and block emails from all other users in AOL 9.0 for Windows. To do this, first open your AOL mail box. Go to the Mail Options menu and select the option "Block Unwanted Mail". This pops up an "AOL Unlimited Use Area" screen. You have to select "Yes" to proceed. This opens the Mail and Spam controls window. Now scroll down in the window till you find an "Additional Spam Filters" heading. Now there is a Select Filter over there. Click the Edit button next to it. Now you have to check the radio button which says "Allow mail only from people I know". ("People I Know" implies all the addresses that are in your address book, buddy list or anyone you wrote an email to or forwarded a email.) Now click the save button to save the new settings. This video shows how to allow email from people that you know, blocking all other emails.