I have a user whose PC has two monitors. Yesterday one of her monitors suddenly no longer had picture (and it was the one that had the Start button and Task Bar, so that meant she couldn’t do any work on her other monitor). I tried to unplug the bad monitor from the PC (so that the remaining monitor would then have everything – the Start button, task bar and desktop icons – on it) but I accidentally unplugged the good monitor. So I plugged that back in and then unplugged the bad monitor, but this caused the good monitor to have no picture as well. I even restarted and still no picture on the good monitor.
Today her PC has picture on that good monitor. I think the problem is that she has an issue with the PC and not the monitor (I removed the “bad” monitor and plugged it into another PC today and so far it works fine) because when I went into her Display Properties, Settings tab, I noticed it looked odd (see attachment for screenshot).
Device Manager says everything is OK. The graphics card (NVIDIA GeForce 8400GS) had an older driver so I updated it (at least I think I did - see page 2 of the attachment to see what I mean), and restarted, but the Settings tab of the Display Properties still looks odd.