plugin does not load

Hello,
It appears that the plugin does not load any more. I get the following error message when I open wordpress:

Failed to load plugin url: http://www.myberlin.nl/wp-content/plugins/facebook-button-plugin/bws_menu/js/shortcode-button.js

What can I do. I tried to uninstall the plugin, but this does not work.

Many thanks.

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