In the network environment, you enable synchronous processing of logon scripts in a Group Policy object (GPO).
Consider the following scenario, you log on to a Windows XP-based computer. Then, within 1 or 2 seconds, you press the Windows Key+L keyboard sequence to lock the computer. In this scenario, the operating system may automatically unlock. This enables the desktop to be accessed. When the desktop can be accessed, all usual actions can be performed in the previously locked user session.
When this problem occurs, if you press Windows Key+L again, nothing happens and the user session remains open. Then, if you press CTRL+ALT+DEL, you receive a message box for the user's credentials.
If you enable the Fast Logon Optimization feature, this problem occurs.