I am using Useful Sharepoint Designer Custom Workflow Activities (dp.sharepoint.workflow.wsp) that contain Activity Send Email with List Attachments. Activity is added as an action to designer workflow which is completed without errors when started. However, mail is not sent. Standard SP action Send Email works fine. I have deployed this custom activities by the book. Web config has authorizedType tag.
My mistake. Activity is working, mail is sent only when list item has attachments. Otherwise, no.