In fact, I had this solution in mind, but I wanted to know if another way could exist. Thanks for your reply. :)

Sorry about the tone, I don't mean it. I just don't know of a nice way to tell people that free software still comes with a price.

Yes, you're right for this point, but my application is targeting PC which displays multimedia messages on screens (LCD or Plasma) and, normally, there are no interactive users on these machines. My application must turn off/on screens when no messages are displayed in order to save LCD/Plasma life time. My solution works well because, for that kind of PC, there are no users, but I want to develop my application properly, and I cannot accept that the screen could turn on without my application. :) Maybe this is not possible on Windows platform to turn off properly the screen. :( The last thing I would say is that I could do that on Atari ST platform, and fifteen years later, I could not do the same thing on Windows platform fifteen years old :confused: ?!! I think this is the progress... Thanks for your response.

Depending on your OS, you might be able to use Terminal Services (sometimes called Remote Desktop) to do this. On some OS's (XP Pro for instance), this will "lock" the machine. It blacks out the screen until you're done with it, then it comes back with the screen locked (like when you do Ctrl-Alt-Delete "Lock Computer"). The machine would then have to be unlocked with a name and password. I'm not sure if there's a way around that. On other OS's (Win2K Server for instance), it allows multiple people to terminal service in at once (2 by default I believe) while the local access is not affected. In this scenario, you'd be working behind the scenes without the customer knowing you're there. If those two don't work for you based upon the OS you're using, you could look into a non-free service. My friend uses one called GotoMyPC link. I know for a fact that GotoMyPC has an option for blacking out the screen. I'm not sure how good it is in general, but the nice thing about these services is you don't have to open up a firewall or port forward a NAT. Hope that helps... I, for one, do not think the problem was that the band was down. I think that the problem may have been that there was a Stonehenge monument on the stage that was in danger of being crushed by a dwarf. -David St. Hubbins