I created a dll using some vision 7.0 functions and Labview 7.0 environment. I call this dll from visual basic. The dll will work fine as long as I don't stop the visual basic program execution. As soon as I stop the program execution the dll will no longer work. I must reload the visual basic environment and the call to the dll will start working again. I created the exact same dll but I created it with vision 6.0 in Labview 6i environment. It works great and has no issues.