Restarting Terminated Worflows
You can restart terminated workflows (workflows with “Cancelled” status) manually or allow automatic restart.
Check the boxes opposite workflows you need to restart and use “Restart” button.
To allow automatic restart, click “Settings” and check the box “Automatic restart of terminated workflows”. If a workflow has “Cancelled” status, it will be automatically restarted.
Note: automatic restart is available only for SharePoint 2010 workflows.