Home → EstiMate Version 1 → Error Messages & Behavioral Problems → Error: I/O 21 when trying to repair/maintain database?
Click O.K. when the message comes up.
Close EstiMate by clicking file>exit or simply the 'X' in the upper right hand corner of the screen.
Double-Click the EstiMate icon to re-open the application.
Click Management> Repair/Maintain data files and then the verify and rebuild button.
This should repair the database and resolve the error.