Blank Window when i start up Node Red

When i start up Node Red, only appears just a blank windows, even though i've re installed Node.Js and Node Red, why could be tha cause???

Welcome to the forum @marccasas

We need a lot more information.
What OS?
What hardware?
How did you install node red?
What version of nodejs?
Are you running the browser on the same computer as node red?
What browser and version?
Open the developer console in the browser and look for errors when you reload the page.