Connecting to external screen or tv

Make sure you've marked the check box next to 'Extend my windows desktop to this monitor' in the settings tab in display properties.
 
Sorry. I'm using Windows 2007 and can't find the check box you're talking about. Can you lead me through it. I've been looking in all the possibilities of display settings. Thanks for your help. Jan
 
Sorry. I'm using Windows 2007 and can't find the check box you're talking about. Can you lead me through it. I've been looking in all the possibilities of display settings. Thanks for your help. Jan
 



Sorry, I can't find what you're telling me. in Windows 7 there is no check box telling this . Any other ideas. Jan