When I run arduino_debug.exe in cmd,it report a exception :jnidispatch(....jna/win32-amd64/...) not found in resource path. I locate jna.jar,the path(win32-amd64) not found.So I download the newest version jna.4.0.1.jar and replace lib/jna.jar,the exception has disappeared.
Run arduino.exe ,the dialog is not come,But the IDE is not opened.No exceptions no Logs and no IDE,only a splash form.
Windows 8.1 pro X64
On my other computers,use the same old jna.jar,also in Windows 8.1 pro X64, was all right.....