A few more details. I need to programmatically (Winforms, VB.NET) check if a site is in the Allowed Sites list of the IE Pop-Up Blocker (IE 7 and 8 and Windows XP, Vista and 7) and if not, add it. The application is fully trusted and I don't want to disable the Pop-Up blocker entirely. To clarify some things, this is for a web-automation application with several users across 3 countries. I want to avoid receiving tons of emails and explaining each time how to add the website to the Allowed Sites manually. Also, some of the users have Google Toolbar installed, which also has a Popup Blocker creating trouble to my app. Can this also be done programmatically?