Also very important logs for diagnosing crashes are the files inside the POSLOG folder. The controller automatically stores information on system state when certain events happen. Events could be e.g. emergency breaks, pushing the deadman switch, certain messages, ... . The files can be opened with a Internet browser and show a lot of useful information like commanded and actual positions, program points, ... .. The Event occurs when the time stamp is zero and you can go back right into the past following the negative integer time stamps. Since there is a limited amount of files from the past you should have a KRCdiag taken right when the problem occurred because KRCDiags archives those files.
Back at KUKA we usually used these files to analyse crashes. More than once we were able to show that not the system but bad programming or crashing the robot in manual mode where the reasons though customers stated otherwise.