These solutions must work in your Mac with given hardware specifications, however you can inform us about any other solution which is successful in solving the Wi-Fi connectivity problem in OS X Yosemite. Open Terminal and type the following command: sudo nvram boot-args'kext-dev-mode1' 3. This is the first solution to fix Wi-Fi connection issue in Mac OS Yosemite however another solution is mentioned below if the above description does not work for you.
It will display an option stating Allow all applications to access this item and you will need to check on this option.
Simply visit Keychain > System > Locate your Wireless Connection and simply click on the last option.
