When you say "wallpaper" do you mean your laptops desktop wallpaper? You should see that as well as your desktop icons. If you see part of your desktop and not all of it, I have to think the resolution and or refresh rate isn't quite compatible with the projectors. Did you try to put a DVD in and see what happens? I also know some laptops have a key combination to turn on/off the external VGA connector. Some allow simultaneous output to both projector and laptop screen and some do not.
I have an HP Pavilion dv1145ea widescreen laptop (running XP Home with service pack 3) which I am trying to connect to a digital projector in order to show a DVD movie at a public meeting tomorrow (that's on Friday 17 October in the UK). Apparently some computers connect easily, but not this one, although somebody else managed it, so I know that it's possible!
I can only get wallpaper to show on the projector screen at present. I was told by HP Total Care that in Control Panel - Display - Settings I should choose Multiple Monitors, with Screen 1 res 1280 x 768, both boxes ticked; and Screen 2 res 1024 x 768, bottom box only ticked.
When I double click the two screens to confirm their identify they both identify as Screen 1, and screen 2 shows default monitor instead of multiple monitors. The projector screen shows either blank or wallpaper. Just once the projector screen showed identity 2, but I don't know how I got there, and it didn't go so far as to show either the icons on the desktop or Windows Media Player.
I think that at some point I should hit either f5, or fn + f5. When I tried that the former had no effect and the latter sent the laptop into a standby routine.
Any help overnight would be very much appreciated