Ah wait, just as I typed the above I now see in the install window “Another Installation is in progress. Please wait to try again” which is strange as only one installation should be running just now. It stopped and asked to wait and offered retry.
I went into task manager and shutdown all installations. There was 2 running but no CPU time being used.
I had this problem when I was trying to install the android (3rd party) stuff as part of my vs2015 installation, but I had an incompatible (older) version of Java installed, and it hung up on that part.
I uninstalled the android SDK and Java, and tried again, and then it worked.
Your problem may be unrelated since it is vs2013, but that’s what worked for me in a similar situation