If you purchase a case for your Samsung Galaxy S II Epic 4G Touch that has a front facial cover with exposure holes for the ear speaker, proximity sensor, light sensor, and camera,the proximity sensor will not work correctly if it is any other color than black.

You don't need a new case. Believe it or not, all you need is a black sharpie or other permanent marker.

I Purchased 2 identical cases, one for my phone and one for my wife's. One all black, and one black with purple. The purple part of her case was what covered the front of the phone (with the holes in it). For some reason, with the purple one, the proximity sensor would not work. At all. But with the black case, it worked fine. I switched them from phone to phone to be sure it was the case. (I found a similar problem with white and pink Otterbox phone cases as well, and the solution was simply a black sharpie).

At first common sense told me that the hole around the sensor was just not big enough, simple enough, so I drilled it out bigger. YOU DON'T HAVE TO DO THIS. It doesn't work. DON'T DO IT!! All you have to do is neatly color the inside of the proximity sensor hole with a black sharpie and it will work just fine.

PROBLEM SOLVED