I'm using the stock supplied Windows 7 so maybe this could happen if someone installed this OS and forgot something or tinkered with services.
Sadly all I can write is that this works fine here.
Bob
I have a Lenovo T510 and a 24" Samsung external monitor in my home office. All is fine when switching between laptop and external monitor (Monitor 2) via the Resolution option.
The problems start when I shot down the laptop while still viewing on the external monitor. When I start up Win 7 again on the laptop (standalone) when disconnected from the external monitor (a physically different location - work office), I get a blank (dark) screen. If I connect a different monitor I get a display on the different external monitor.
So using the Resolution, I change the monitor to view only on the laptop and the display switches to the laptop. All good. But when I disconnect the VGA cable the screen goes blank, even though the Resltion option is set to display only on Monitor 1. So I cannot use the laptop as a standalone computer. I have to wait til I get home and plug in the Samsung monitor.
Is there any way I can force Windows 7 to boot only to the laptop monitor?

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