Same URL in "Duplicate Content" and "Blocked by robots.txt"?

[alsvik]

How can the same URL show up in Seomoz Crawl Diagnostics "Most common errors and warnings" in both the "Duplicate Content"-list and the "Blocked by robots.txt"-list?

Shouldnt the latter exclude it from the first list?

[ChrisCountey]

I think that both of these tools are mutually exclusive. It does not take into consideration that a page blocked to spiders won't count against you in terms of duplicate content, but maybe it should!

[alsvik]

It's kinda strange. I would expect all URLs blocked by robots.txt to NOT show up anywhere on Seomoz.