Hey guys, I searched and found a thread like this but it was closed so I'm gonna start a new one.

I just started Diablo and wanted to change the buttons to my liking. My hand curves nicely with shift, s, d, f, and space so I wanted to use these keys. Shift, s, d, and f would be attack 1/2/3/4. However, I'm unable to bind shift as attack 1. Am I making a stupid mistake or was it designed to be like this?