I have several VS 2008 C# applications that I have developed that interface with an accounting application. They all work fine with one exception. What I have noticed is if any of these programs are called and the resulting data set is empty, all subesequent calls to any other programs are disabled. The only solution is to leave the accounting applicaiton and come back in. When I say disabled, what I mean is what you execute the keystroke to call them they return no data even though there is qualifying data to be returned. It seems like somehow my windows do not close properly when the dataset is null. How do I insure that the windows do close properly even if the dataset is null? Do I need to add some code to an event someplace?