SharePoint 2010 Migration Error: A duplicate content type name "Resource" was found

During the migration from SharePoint 2007 to 2010 – we received "A duplicate content type name ‘Resource’ was found” error.

To remove this error, we have rename “Resource” content type to “Resource1” into SharePoint 2007 site and restored the content database again to make sure that we were clean for this error.

Reference Link: http://go4answers.webhost4life.com/Example/sp2010-upgrade-eror-duplicate-content-23253.aspx