reference location lost when installing ver1.6.4 version of Arduino

while I am in Arduino I select help-reference. The screen appears but it is blank, after 3 to 5 minutes the reference page appears. It is from Arduino website. The address shows "C:\Program Files (x86)\Arduino\reference\arduino.cc\en\Reference\HomePage.html" I can't find anywhere to point to the reference file which is in the Arduino program directory. what have I done wrong? Help