Is there way that I can prevent the machine from locking out? The problem I have is that when I run scripts from QC the machine locks out (I need to press Ctrl+Alt+Del buttons) and all scripts fail due to that. How can I overcome this problem?
I would always consider running a virtual machine on your desktop machine.
The settings of the virtual machine can be modified to never lock.
If you want to lock your desktop machine the virtual machine continues to run your tests unaffected.
Microsoft virtual PC can be obtained for free and is not too difficult to configure.
This approach is a more secure solution than trying to circumvent the desktop configuration to lock after a specified period of inactivity, as it allows you to lock your desktop whenever the need arises.