The problem that I am having is that my computer, a Vaio Z laptop (VPCZ133GXB to get specific) is suddenly unable to connect to an external monitor over HDMI, as it always had been able to. I can connect with a VGA cable, but the resolution is low and the screen just flickers like crazy. I think the problem has something to do with another bizarre symptom, which is that when I go into the Screen Resolution section under Display in the control panel, Display 1 is always set to "Display device on: VGA," even when no VGA is plugged in. I was giving a presentation the other day via a VGA projector, so I'm wondering if I somehow messed up this setting. Anyway, here's a screenshot to what I see under Screen Resolution as the default. Does anyone have any ideas, short of an entire reformat and reinstallation of all my drivers? I really need this external display to work.

Hi, For this issue, I suggest that upgrade the driver for the graphics first, some dirvers problem may lead to the error for interface recognition .