If you are having issues with the setup, try the portable client.
Alternatively, if download speed is slow or unavailable, you can try this Dropbox Mirror.
Windows 7 System Pack 1 or later
2 GB of RAM or more
2 GHz processor
DirectX9 compatible video card
1024x768 resolution or greater
Internet Explorer 11
1. Run the Setup by right click > Run as administrator.
2. Follow the instructions given in the setup.
3. Run the launcher to update to the latest version and start playing!