Problem Loading Page: File not Found

I cant give you the technical answer, but basically clearing your cache, cookies etc works, I guess because you generally change code in pages that have already loaded, so they are already stored and cached, and certain code changes is tricky for the browser to update within your current cookies, temp, cache etc

All I know is, its sometimes required depending on what code you change.

as for your site,
A few of the images didnt load for me, and I have obviously never had the sites details in my browser

one of the images was this one
"Grand Canyon Trails. By cartographer Kent Schulte. A superior topographic map. $9.95"

Its the first image in the list

And a page refresh sorted it out.

Some other things I will point out
map of  Grand Canyon National Park.   This is  truly a hiker friendly map and will prove to be a'
Not sure why you used   there?

And when I look at your source code, there seems to be an obscene amount of
Seemingly much more than what could possibly be required by the amount of content on your page
In fact, you have 568 entries of .

This may be correct, but just thought i'd point it out.

Good luck

I found a review on Expression Web Designer, part of which is as follows:

"The best thing is the software discover so many coding errors in my existing websites that Dreamweaver just ignored. And it is just so easy to correct these errors because Expression Web tells me exactly where it is and what to do about it. If you care about conforming to the stricter standards of XML and XHTML, there is no better tools for website development than Expression Web."

Is that possible? That it would find the errors and tell me what to do?

Or as an alternative: Would a lot of time/commitment be required to learn enough about the standards through reading, etc to be able to spot the errors and correct them myself?