It appears l like you copied the site over, but you might be missing some of the content. The 404 is occuring because when the url of http://marketweb20.com/forex/forexvideos/ is searched - it literally does not exist. If this is a product of the Wordpress program building that link, then you will need to rebuild your permalinks. You can do this by first saving an custom permalinks (copying them to a text file) - you will need to login to the Wordpress Administrator to do this. After you have copied your custom link, switch the permalinks to DEFAULT and save. After it's saved, go back and re-create the custom link based on what you had saved previously. This should rebuild the links you may have had before.