Sherry,

> The VPF app will be closed after the imaging activated. Each time when a user presses "V" to view an image file the imaging app still open from the previouse call but the VFP APP will be called but the object is nolong there.
>I think if I can use the object reference from the first time the object created it will work, otherwise, I don't think there is anything else would help me. Thank you for being so patient with me.

Maybe someone else has a better idea, but the only thing I can suggest is to do everything in your VFP app, including the user pressing "V" to view an image file. Can you re-think things to have VFP read a directory, put the images into a listing, and let the user choose? If you can do that, I don't think you'll have a problem with the imaging app instancing.