After years of frustration and hundreds of millions of dollars lost on a system that didn't work, the FBI has finally deployed a new $451 million computer system called Sentinel. The web-based interface allows agents to widely search all FBI case files and data as they work investigations and track down leads, effectively moving FBI agents and analysts away from paper based files to a streamlined computer program. The system allows agents to conduct searches of related case information to connect the dots." The FBI was sharply criticized after the 9/11 attacks for failing to piece together information about suspected terrorists obtaining flight training in the United States. The FBI was first warned in July 2001 by FBI Agent Ken Williams, who was assigned to the Phoenix Field Office, that individuals associated with Osama Bin Laden were undertaking a coordinated effort to obtain flight training in Arizona. The memo he wrote recommending that the FBI have liaison with flight schools in their areas was not widely read or acted upon. In August 2001 officials at FBI headquarters did not realize the significance of the arrest of Zacarias Moussaoui who was seeking flight training in Minnesota and had financial connections to the 9/11 hijackers.