Hey Shiraz:
What version of DNN was the skin made for? If it's 3.x, there are some minor changes that must be made to the ascx file (I don't use the html/xml procedure). Is this an ascx skin or did you have an html/xml skin that you uploaded?
The skin, if successfully uploaded should be in your /Portals/_default/Skins folder (if you installed them as host). If you want to just skip a step and have the ascx files, you can just place the skin folder in the /Portals/_default/Skins folder and that should work. Just make sure that your skin ascx file has a first line that looks like the following:<%@ Control language="vb" CodeBehind="~/admin/Skins/skin.vb" AutoEventWireup="false" Explicit="True" Inherits="DotNetNuke.UI.Skins.Skin" %>Hope this helps.