AhnLab Policy Center 4.0 (APC 4.0) is a centralized management solution for security products, offering significant improvements in user convenience and data reliability. Key features include emergency security alerts, desktop management, and a monitoring center for real-time updates on security status. The upgrade policy allows previous users of APC 3.0 to upgrade for free if they still have remaining usage time, with promotional discounts available for new and existing customers.