You can disable screen saver. See Disable/Enable Window's Screen Saver File #9403

>Does anybody here know "Appctrl.exe"? I'm using this program to automate a series of keystrokes in Visual Foxpro 6.
>
>The problem is that it is not able to execute certain instructions that I want it to do when the screensaver/screen is locked (run smoothly when screen is active). I have checked the setting in the Power options - Harddisk is never switch off nor the system can go into hibernate mode.
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>Please advise if you have overcome this problem. Thanks.
>
>SKY