Why Does the Workflow Status Disappear in SharePoint 2010?

Symptoms

In SharePoint 2010, the workflow status links for a work item disappear over time.

Cause

By default, Microsoft SharePoint Server 2010 runs a daily Workflow Auto Cleanup job to permanently delete workflow instances and related task entries that still exist 60 days after a workflow is completed or canceled. Workflow history items themselves are not deleted, but the entry point to view them on the status page for a particular instance of a workflow will no longer be available.

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