help about the 3d view rotation

Hi!: i used to be able to (press MMB release it and rotate my 3d view). “1 day ago”
i had to re install blender and now i cant find that feature anywhere.

this is important as this feature helps me alot with my hand and wrist issues i have .

cant remember how i did it ,or what extension i installed.

i use the last release at ( no night builds )

thanks in advance

File/User Preferences/Input/3D view/Rotate view
Change Press>Click