After performing a manual installation of a reference computer, installing several applications, and configuring a multitude of settings, Howard runs Sysprep.exe with the /generalize parameter, opens a command prompt window, and attempts to capture an image of the computer using ImageX.exe. When he types the ImageX.exe command and presses enter, an error message appears, stating, "The process cannot access the file because it is being used by another process." What has gone wrong, and what does Howard have to do to capture an image of the reference computer?