Porsche

My external hard drive has stopped working! it a lacie (design by f*a*porsche) its hooked up to my mac mini. its pluged in correctly and has worked but now it isnt. the little light is red. when i turn it off then turn it back on it flashes green then goes back to red then it turns green for 3 seconds and goes back to red. all of my songs on itunes have that little ! next to them. how do i fix it?

Maybe this? http://forums.macrumors.com/archive/index.php/t-158158.html