Are you using mxe build of octave? It does not work with windows 8.
I ran 3.7.7+ with GUI on Win 8 (until we had to reinstall Win7as other applications didn't yet run in Win8).
All I had to do is adapt the Properties (right click on the desktop or Start menu item (if you use a Start menu add-in, like e.g. Iobit) and add the -i --line-editing flag.
Make sure you call octave-gui.exe rather than octave.