User blog comment:*mynameischrome*/Games not working./@comment-26408796-20141226013248

Here, try this: If they extract properly, then you're good to go!
 * Navigate to the %HOMEDRIVE%\Users\%USERNAME%\AppData\Local\ROBLOX\Versions folder. (You can just copy and paste that into the explorer bar)
 * Clear out any folders in there. Just to be safe, do not delete any executable (.exe) files.
 * (Optional, probably unneeded) If they appear in your Program Files list, uninstall them if possible. If they say the uninstaller is not present, then you can skip this.
 * (Optional, but recommended) Restart your PC.
 * Download the latest versions of ROBLOX Player Launcher and ROBLOX Studio Launcher from the site.