In Windows 7 Microsoft has introduced a very nice feature, the ability to extend/duplicate your desktop to an external screen.
In Windows XP I found it to be very, very annoying whenever I had to use a laptop when presenting that wasn’t mine since every single vendor had their own shortkeys for switching to an extenal screen. But this was only to duplicate the to the external screen… when you wanted to extend the desktop, you had to open the screen properties in Windows and select that… bloody annoying.
And then there was Windows 7. Just by pressing “WinKey + P” you would get the screen below:
Very easy and user friendly, me like!
Now, this afternoon I was at one of my customers which is a school for higher education. They decided to attach a second monitor to all the computers in the science department.
But the ‘issue’ was that a manual action was required to extend the screen to the second screen.
What they didn’t knew was that the screen as shown in the screenshot above can be called through the command “displayswitch.exe”… and it has parameters! Specifically…
| Parameter | Description |
| /internal | Disconnect projector |
| /clond | Duplicate screen |
| /extend | Extend screen |
| /external | Projector only (disconnect local) |
So, simply by deploying this command to those devices through some kind of central method no user interaction is required 
