If you are like me, my job can involve showing demos or presentation slides to an audience via an LCD projector. The technical gorp that I always hated was resizing my nice big 1400×1050 desktop to fit a small 1024×768 projector, and then enabling the external video port. When I restored my desktop, my open windows weren’t always restored to their original size and location after being scrunched by the 1024×768 resizing. Additionally, any instant messages or screen operations I wanted to do weren’t private – the audience could see them because the LCD projector was an exact replica of my laptop screen.

So here is the solution for Windows XP users: Dualview. You can set up the LCD projector to act like a 2nd independent screen that can coexist with your laptop desktop. So keep your laptop desktop intact and its original size, but you can use the LCD projector as a second desktop that is an extension of the first. The LCD projector starts clean, then open your presentation application, then drag the presentation application off the laptop screen until it appears on the LCD projector. That is the only thing that appears on the LCD projector. So if any instant messages come in during my presentation, I can see it on my laptop screen but the audience won’t see it (i.e., prompts from a friendly mole in the audience). Even better, I can look at softcopy presentation notes while the audience sees my presentation slides.

The only downside is that I need to be able to see the LCD projector screen, since that is the only way to see what is happening on this second desktop. But the upside is that I can configure it and just leave it like that permanently. No more having to resize the desktop to fit the projector and undoing the damage afterwards. Just plug in the projector’s external video cable and go. (I do find that Dualview gets automatically disabled after I suspend or reboot without the projector cable attached, but a few simple clicks can re-enable it.)

Read this article to learn how to enable Dualview. Hopefully your laptop supports it as well as mine, not all do. For the external desktop, size it to be optimized for the LCD projector (usually 1024×768).

Before attempting to drag a window between desktops, make sure that you un-maximize it. Otherwise you can’t drag it. Also be careful after dragging not to drop it in a way that the menu bar controls don’t appear on any screen. Since most applications (including PowerPoint) remember their last screen position when they are restarted, it is possible for an application to restart on the projector desktop without being able to see it such as when the projector is turned off or the cable is disconnected – if this happens, disable Dualview and it should come back to the laptop desktop. Enjoy!