New users of an application system, especially computer novices, can become confused and frus-trated after experiencing the first, perhaps not recoverable error situations during the early stages of explora-tion and learning. System facilities, which let users UNDO and REDO executed commands, are suggested tobe an aid for active learning and can be used as a method for systematic exploration through recoveringfrom unknown and newly explored (perhaps wrong) system states by cancelling executed commands withUNDO. An explorative learning experiment on a commercial graphics editor with a modified user inter-face revealed reasons, why one-step recall UNDO does not guarantee successful explorative learning of acomplex cognitive skill such as graphics editing on computer. New users of an application system, especially computer novices, can become confused and frus-trated after experiencing the first, perhaps not recoverable error situations during the early stages of explora- tion and learning. System facilities, which let users UNDO and REDO execute commands , are suggested to be an aid for active learning and can be used as a method for systematic exploration through recoveringfrom unknown and newly explored (perhaps wrong) system states by canceling executed commands withUNDO. An explorative learning experiment on a commercial graphics editor with a modified user inter-face insight reasons, why one-step recall UNDO does not guarantee successful explorative learning of acomplex cognitive skill such as graphics editing on computer.