I have a MacBook Pro (13-inch, Mid 2012) and only recently I could buy a VGA mini displayPort adapter. The adapter is good as I have used it with my brother's 15-inch MacBook Pro and two different monitors and VGA cable are ok because of the same reason. The (almost always hidden) Detect Displays button does nothing and the Mac cannot recognise any monitor I connect to it.
I use El Capitan and all the updates as of today have been made. Also I do not have any other adapter (DVI or HDMI) to test the port and I am not likely to have one soon.
Thanks in advance