Google Chrome extensions not working for me?

I have google chrome and every time i download an extension it doesn't work. it actually saves the file instead of installing it to google chrome. my google chrome is up to date and still cant use them. can someone help me?|||on what computer do you use chrome? If it's a mac, it won't work. If not you could just try to open the file right away or right-click on the file that was downloaded and go to open with and then chrome.