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https://nishantrana.me/2015/10/07/no-plugins-have-been-selected-from-the-list-please-select-at-least-one-and-try-again-error-while-trying-to-register-custom-workflow-activity-in-crm-2013-online/
No plugins have been selected from the list. Please select at least one and try again error while trying to register Custom Workflow Activity in CRM 2013 Online