If a message box with the error "The default Results Directory is locked" appears when you replay a script in VuGen after a VuGen crash. The crash locks the current Results directory and no longer allows results to be written to it.
To resolve this issue, Check for any instance of mmdrv.exe in the Task Manager
Close VuGen, and check for any instance of mmdrv.exe in the Task Manager; if there is one, end this process. This will unlock the current result directory.