I had a similar problem. I am guessing that you have used standard html img tags for your images. This is fine in the master page or pages at the same level of the master page, but as soon as you start adding pages in subfolders the url to the image in the new page is not correct. To fix this I used asp:Img control instead and it is able to resolve the url relative to the root folder as long as it is set to runat="server" and ImageUrl property has the prefix of "~/" followed by the image location eg "~/images/my_image.jpg". I am a newbie at all this, and I may have got this wrong, but that's what worked for me.