On my sons computer (Sony Viao with Windows 8) we have tried to download the chrome extensions for chromecast but it fails. We get an error message that says it could not create a download directory. The directory it tries to download is under his profile under users under appdata and has some random numbers involved (each time different directory). It works on other computers (mine is windows 7) but chromecast is for him and not having it work on his computer is just not good. Any advice / assistance is greatly appreciated.