One of my client has got a domain with 2 extension .net and .com .com domain is the working domain where .net domain isn't using at all the content is same but hosted twice, From SEO view, what I have to do when I have 2 domains with same content. Tow domains are same but with different extension. The content is same but hosted twice. thanks for your comments
301 redirect .net to .com would be the obvious thing to do otherwise you may get hit for duplicate content on one of them.
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301 redirecting the .net to the .com like vagrant said is probably the best solution on this one so SE's dont think its duplicate content.
Yes redirection, never use the same content on two sites, exccept you are an authority and have the content in two different languages.
the best way would be to remove the content from the .net, put the content only on the working .com site, and 301 the .net domain to .com