The fact that the company's webserver has returned the infamous
HTTP error 404
to a URL does not mean that the resource does not exist.
It only means that the webserver has decided that
for you this resource does not exist.
The webserver can identify you as a paying customer by many methods,
chief among them is an identifying
HTTP cookie
stored in your browser.
When the cookie is not found, the webserver will usually ask you to login,
and if successful will then return that cookie.
The question is then why is Googlebot allowed access, but you are not ?
Googlebot will eventually discover almost any website,
but the webmaster can request an early visit by using the tools contained in
Get your content on Google. He can also direct the bot to certain folders by using a
Robots.txt file.
An example of such a file is :
User-agent: googlebot
User-agent: google
User-agent: bingbot
User-agent: bing
Disallow: /bedven/bedrijf/
Crawl-delay: 10
User-agent: *
Disallow: /
The bot identifies itself by using in the header of the HTTP request a
User agent
tag, for example googlebot.
However, assuming the identity of Googlebot is not an easy matter.
The website can easily
verify the bot's identity
by doing a
reverse DNS lookup
on the accessing IP address.
The returned domain name must in that case be either googlebot.com
or google.com, which is something that you yourself cannot fake.
If you fully control your webserver, for example via PHP,
you can duplicate this mechanism and create what is called a
"membership website".
Such software is called
Membership Software.
If you are not a PHP programmer, or are unwilling for such an investment of
your time, there exist many open-source software alternatives,
but also lots of commercial products that will compete for your business.
Be very critical if you decide to choose one, and check it thoroughly
on the web for reviews.
For more information see these resources that I found via a search
(not necessarily the best ones, and some are quite commercial in nature,
but they will get you started) :