Recovery from human operator error is key to system dependability: users are usually the main source for incorrect data, and this data can render a system unusable. Although current management information systems allow for the reversal of some processes, they don't offer an undo function to correct the errors human operators might introduce while editing data. The authors propose a method for correcting this potential problem with a new undo function that allows the recovery of previous states even after records have changed. While developing a new open-source, Web-based enterprise resource planning (ERP) system, we at IT solutions provider Tecnicia realized the added value of such an undo function. The undo function is a basic feature of recovery-oriented computing (ROC), which aims to increase dependability by reducing repair and recovery time.