I've signed up to a forum using my hotmail email address and for some reason my forum profile picture comes up automatically as an image I uploaded somewhere on my hotmail account before. I can't remember how to change this image. To be clear, it is not the same image you see on the top right when you sign in to your hotmail emails. 

Does anyone know what I'm talking about and can anyone tell me where I can change that image?

Thanks for reading!