The method described below can be used to start a workflow for SharePoint 2007 or SharePoint 2010 at a specific time and then repeat periodically (every day).
You can start workflow for multiple items at the same time.
Also it is not required to use Microsoft Visual Studio.
Periodic Workflow Processing A useful implementation of this technique allows you to configure workflows to run as background tasks at a specific time instead of being triggered by a user manually, or after creating or modifying a list item. This allows you to process SharePoint data when the SharePoint environment is not being used as long as tasks need to complete.
For example, this method can be used to configure a looping timer workflow that supposed to run every day (18:00) to perform calculations and processing on a list item before emailing a reminder, or details to a user associated with the list item or document.
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