After having a problem with the HDMI cable on Samsung Syncmaster 1600x900, I changed it to a DisplayPort to VGA adapter, but now it is not detecting the monitor correctly.
The available resolutions for it is now 1280x1024 & 800x600. I have shifted already to custom resolution of 1280x768 by selecting a custom resolution after pressing option and then selecting scaled displays.
But I want it to have its original resolution.
It feels like it has supposed my monitor to be secondary display.
P.S. : Already have deleted com.apple.windowserver.plist in Safe Mode.