Missing Completed Workflows History

REF: http://social.msdn.microsoft.com/Forums/en/sharepointworkflow/thread/b15b27e2-3033-418b-9731-968273d7423e

P: I cannot find any workflow histories on approved documents that were approved 2 months or more ago.

A: The workflow data is purged from the MOSS Workflow database table after 60 days. Based on calls to Microsoft about this, it was by design and for performance reasons. However, what good it the workflow functionality if proof of the workflows are deleted? How can companies meet various industry auditing requirements for SOX, ISO, TS, etc? Microsoft gave us only one option: changing the 60 days to something higher by writing a script modifying the SPWorkflowTemplate.AutoCleanupDays property of the workflow associations. But this does not bring the deleted data back?

For anyone seriously considering using the MOSS workflows, I would advise you disable the "Workflow Auto Cleanup" timer service in Central Admin (central --> Operations -->Timer Job Definitions) to prevent any further deletions of your workflow data. A lot of agonizing work went into researching this problem because it was not documented by Microsoft. Not even the MOSS database schema. I had to reverse engineer the database and study the stored procedures to uncover the truth about what happened to my data.

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