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You can’t uninstall it from marketplace if you don’t install the plugin with the marketplace…

Use:

<li style="background-color: white; border: 0px; font-family: Arial, 'Liberation Sans', 'DejaVu Sans', sans-serif; font-size: 14px; line-height: 18px; margin: 0px; padding: 0px; vertical-align: baseline; word-wrap: break-word;">Click on Help > About Eclipse</li><li style="background-color: white; border: 0px; font-family: Arial, 'Liberation Sans', 'DejaVu Sans', sans-serif; font-size: 14px; line-height: 18px; margin: 0px; padding: 0px; vertical-align: baseline; word-wrap: break-word;">Click on the “Installation Details” button</li><li style="background-color: white; border: 0px; font-family: Arial, 'Liberation Sans', 'DejaVu Sans', sans-serif; font-size: 14px; line-height: 18px; margin: 0px; padding: 0px; vertical-align: baseline; word-wrap: break-word;">Select all the installed software you want to uninstall</li><li style="background-color: white; border: 0px; font-family: Arial, 'Liberation Sans', 'DejaVu Sans', sans-serif; font-size: 14px; line-height: 18px; margin: 0px; padding: 0px; vertical-align: baseline; word-wrap: break-word;">Click “Uninstall …”</li>

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