That's unusually generous and tolerant!

Yes, in the address bar, I see what you mean.

I'd strongly advise against that.  By the duck test, "If it looks like an error page and quacks like an error page..." Based on posts in other forums, AdSense is pretty strict, and once you're banned, you might not have much of a shot at getting back in unless your site is big enough that it's worth their time to negotiate with you.  I think they also have a requirement that AdSense can only go on content pages, so unless you put articles on your error pages, they'd still fail that test. Splitting hairs with the terminology isn't worth the risk because you'll never get the opportunity to argue your point with them. 

One thing you could do, as long as the pages the hackers created didn't have obvious porn page names, is create your own pages of those same names, with whatever content you want to put on them. Not sure I'd try that myself, but it's a devilish idea.

I'm sorry I don't know the definitive answer to this question. I believe the error pages are served as .shtml, with the name of the originally requested page inserted into the text. Come to think of it, I think the important concept is that the result CODE of the returned packet is 404. Regardless of what text is on the page, that code is a formal HTTP notification that the page does not exist, and is an error code. So I guess that really does answer the question. It is an error page regardless of how it's rendered. The Apache documentation might have more info. http://httpd.apache.org/docs/1.3/.

I did some testing and found the following:

Using the lunarpages cpanel you can create a custom 404 page that is a .shtml file. Users who don't have much developer experience should probably go this route.

Alternatively, you can add a line to the .htaccess file to use a custom 404 file that is an html, php, etc. Just add a line similar to the following:


or


The returned page still uses the bad/original url, and still has the 404 code in the html header, so will still show up as an error page, even though you've customized it.

In your htaccess access use
ErrorDocument 404 http://www.yoursite.com/error_page.php
instead of
ErrorDocument 404 /error_page.php

.htaccess commands generally apply to the folder they're in and all folders beneath that point unless they're overridden by commands in lower-level .htaccess files, so you should be able to put it only in your public_html/.htaccess file. That's the general rule, anyway; I have no experience with the ErrorDocument command.

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From earlier in this thread:


This wasn't a good idea because it acknowledges the pages as belonging to you. That is, as long as those page names exist, they'll remain in search engine caches. If someone runs across "your" cached porn pages in a search engine, they'll wonder why your site used to have pages of that type. Much better to disavow ownership of the pages by deleting them as norm_256 apparently did. When the search engines get 404 errors, they'll gradually purge the cached pages.