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I had two websites. 6 months ago my second website expired and now I want to merge the blog content of second website into first website.
Will it give any negative impact on SEO of first website? What must be taken care of in this process?
It depends on how strong is your first website. If it's strong then you should not observe negative impact. To be save I recommend you to redirect (301) each page of your second website to the new URL.
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