Laptop Screen Turning Black

[gastwo]

Hi.
we have a laptop (vista) with a screen that turns black immediately after windows loads up. However, if I plug in a monitor, both screens will work - laptop and monitor. If I unplug the monitor, the laptop screen goes back to black...

Any ideas?
ATB
Shaun.

[gastwo]

Answered my own question!

I tried 'restore' from a month previous, and it's now back to normal. Still no idea why it happened though...