I've seen many attempts to create a viable CMS that will be indexed by the search engines. Many times the programmers make mistakes in their attempt to be fancy.

These are the mistakes I have seen. Some may not consider them mistakes while others may agree with me.

1. JavaScript links
2. urlencoded session variables
3. urlencoded links using ? and &
4. no site map
5. lack of adequate text links
6. Server load, response, incomplete page presentation
7. Database not repsonding correctly

That is not in any particular order of importance. But they are things I have seen that can stop search engines in their tracks.

If a search engine attempts to call the same page more than once during the same session/visit then there is definitely something wrong with the presentation/server response. It may also be due to the 'bot' finding the same link with "hash" (#) attributes in the links on a page.

Again, I hope this helps everyone.

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Lee Roberts