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It's quite possible that the changes to the link structure affected the way PageRank is flowing through the site and thus the authority of pages.  It's also possible that changes in Google (like the Penguin 2 update, the EMD update, and others) have affected the PageRank of both pages and the entire site and that those effects just happen to coincide with the website move. Without a detailed investigation into the site, I can't really say what may have caused the problem and, even with a detailed investigation, it may not be possible to figure it out at this point.  It may be better to simply evaluate the site as it is now.  Look for ways you can improve the on-page optimization and internal link structure first.  Then work on creating great content, connecting with others, and building up the authority of the site. Kurt PS - The other thing to keep in mind is that the Google Toolbar PageRank isn't reliable at all.  Even Matt Cutts has said not to pay much attention to it.  I would focus more on traffic and rankings than the Toolbar PR.