A method for finding the cause of an error or unexpected behavior of a software application includes providing a list of steps to be executed in order to achieve a certain behavior of the application in a usage scenario and providing a decision tree corresponding with the usage scenario. The decision tree comprises decision nodes that correspond with the steps in the sequence of steps to be executed and leaf nodes indicating one or more possible solutions. The method includes scanning log files to determine whether a step in the list of steps to be executed has not been executed and traversing the decision tree when a step in the list of steps has not been executed. A leaf node of the decision tree that corresponds to a non-executed step is determined and a solution is extracted from the determined leaf node.