I modified the Web.sitemap exactly as suggested in the book page 245. For example (only part of the exercise is shown here):
<siteMapNode url="~/" title="Home" description="Home"><siteMapNode url="~/Default" title="Home" description="Go to the homepage" />
<siteMapNode url="~/Reviews/Default" title="Reviews" description="Reviews Published on this site" >
<siteMapNode url="~/Reviews/AllByGenre" title="By Genre" description="All Reviews Grouped By Genre" />
<siteMapNode url="~/Reviews/All" title="All Reviews" description="All Reviews" />
</siteMapNode>
on Ctrl+F5 the following error is displayed:
HTTP Error 404.0 - Not Found
The resource you are looking for has been removed, had its name changed, or is temporarily unavailable.
Most likely causes:
The directory or file specified does not exist on the Web server.
The URL contains a typographical error.
A custom filter or module, such as URLScan, restricts access to the file.
After multiple tries, and finally on changing the Web.sitemap file to include the extension of the files".aspx", the site runs as expected. The part of the code extracted above and changed to the following:
<siteMapNode url="~/" title="Home" description="Home"><siteMapNode url="~/Default.aspx" title="Home" description="Go to the homepage" />
<siteMapNode url="~/Reviews/Default.aspx" title="Reviews" description="Reviews Published on this site" >
<siteMapNode url="~/Reviews/AllByGenre.aspx" title="By Genre" description="All Reviews Grouped By Genre" />
<siteMapNode url="~/Reviews/All.aspx" title="All Reviews" description="All Reviews" />
</siteMapNode>
Acknowledging that the code without the extension works when implementing the Extension-less URLs on page 263. (Note: to reproduce the error, I had to remove the applied Extension-less exercise).