Hi License Developer,
There have been some issues in our latest release with the control designers and social bookmarks. Please try to go to the advanced tab, locate the social bookmarks property and then enable it there. This issue has already been fixed for the new release.
Basically, what the feature does is that is allows the visitors to submit the content to various social sites, like digg, del.icio.us and so on.
Let us know if that solves your problem. If not, please attach the following folder from your site : ~/Sitefinity/ControlTemplates/Libraries and we will inspect it and come up with the solution.
Thank you for getting in touch with us.
the Telerik team
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