How to resolve non-indexable pages issue.

Hi,

I am using a Firefox add-on tool called SEO doctor, which check each page of your site just by one click. So, I used it in my site and no matter which ever thread I click it says it is not index-able. My homepage, articles and blogs section is index-able but not thread. If I see all threads it says its index-able but when I click on thread to see all posts, it says not index-able. I have attached a screen shot that shows the result. The tool says "page is not indexable because it has conical URL set ...." I did google search and found this "Suggestion: Remove noindex from category pages when it can be used for siloing highly related content." Can someone please advice me how to solve this issue?

Thanks