SharePoint 2010 offers many more features than SharePoint 3.0 (2007) and it is only natural for an organization to want to upgrade a site to 2010. However the upgrade process from 3.0 to 2010 is not a streamlined process, and there is no one process to perfectly migrate all site content from one version to the other. Largely any site created in 3.0 will have to be built anew in 2010.
The best approach for any organization wishing to upgrade would be to build templates and lists ahead of time in a different SharePoint site (please contact email@example.com for options), backup the content and data files of the current site, and then perform the migration. Depending on the size of the site, it can be a very tedious process, please contact our support desk for help firstname.lastname@example.org.
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