Maybe try to have a look through this page, It might help you solve the problem. https://productforums.google.com/forum/#!category-topic/chrome/discuss-chrome/windows7/Stable/RR7hyy0V7Io
I had the same problem, but instead of using Windows Defender, I use a proper anti-virus program (Kaspersky). Then I just disable Windows Defender in the control panel. If you don't find anything to help you, try doing what i suggested to do.