You may have inherited a Tableau Workbook, with a mystery location for the extract, or the past admins’ local machine!
Go ahead and use this knowledge base article to remove, and regenerate the extract:
If you happen to be sharing your extracts on a network drive, then use UNC path format as shown in this knowledge base article:
As I learned recently, an extract is useful as it avoids using a live connection to your database, and allows you and your business customers to have better Workbook loading performance.
Set a schedule for your extract and then it will refresh just in time for your users on the schedule you set!
A nice Tableau article below on Performance tuning your workbooks: