Much better. The first thing that happens is that c:\ATG\AFT_Station\config\Product.cfg is read and the information in the PRODUCTS section is extracted and written to the listbox control. Make sure this file exists but since you do have the list populated, this is probably not the problem. There is a sequence structure and in the second sequence, there is a while loop that constantly spins and waits for a selection. This is not the best way to do something like this (an event structure would be much better) and you should never have a while loop without a wait statement in it. A wait of 100-200 ms would be fine and allow the os to respond to user events. Otherwise, the while loop will hog the cpu.