If your list is not being cleared, I would suspect there is a problem with the list handle you pass to ListClear(). You can put a breakpoint on the ListClear() function. When the program pauses at that point, point to the parameter you're passing to ListClear to see its value. Make sure you don't have a variable scope problem. Does the ListClear() function see the same value as was returned by the ListCreate function? Do you check that the value returned by ListCreate is >0? (0 = error creating list).
Look at ...\CVI\samples\toolbox\list.prj that shipped with CVI. It doesn't include ListClear, but it shows how to create and use Lists from the Programmers Toolbox. To see some more help, in your program, right-click on any List function (e.g. ListClear) and selec
t Recall Function Panel. In the Function Panel window, click on Help >> Function >> Class Help.