Whisper32 error message

When I add or edit data in Whisper32 and then try to exit I get a message box which says 'Save Changes to (file name)?' and the following options: Yes, No, Cancel. If I choose Yes, I get an error beep, an error box that says Whisper32 and has a red circle with a white X in it. The message in the box says 'No error occurred' but it won't let me exit the program. The only way to exit is to choose the 'No' option but then my updated information is not saved. Does anybody know why this is happening and how I can get around it? Thanks