What causes the Eyedropper to change all samples to white?
My Eyedropper has suddenly started changing all samples to white. No matter what area of an image I click it samples white, this is regardless of sample size or modifier keys. If I manually select a color with the Color Picker, and then sample an area of the image with the Eyedropper, same result, white. All of my other tools are working correctly. I tried resetting the tools, I verified my documents settings are correct, I restarted Photoshop, restarted the computer...nothing.
Just found out the answer: quick mask mode
if your in CS6, there's a button at the bottom left hand corner of the toolbox with a dotted circle in it, click it, and you'll be able to select colours again