PROBLEM: Audit Log reporting not enough storage space available, even though all drives have sufficient free space on server. The error in the logs is similar to the excerpt below:
Failed processing case 'Sample' with ID  in queue: Sample.Start. Error message was: Failed to process completed case in QCompletionsThread: ProcessCompleted case failed in MoveCaseToServer. File move failed. Error=Failed to copy file [\\18.104.22.168\CAPSYSProcessing$\Sample\bac44482-9856-4a11-9da3-35e1bb77dfca.batch\batch.flg] to [C:\Windows\capsysserver\bac44482-9856-4a11-9da3-35e1bb77dfca\batch.flg]. Error was : Not enough storage is available to process this command.
.. Case will be retried in 3 minutes.
RESOLUTION: Database growth settings set too low, added 1GB to database and increased growth to 5%.