Found nothing wrong with your code...works fine for me. I am working in the app.path, to which I have read/write privileges.
Are you using a path to which you might not have those privileges? Try app.path first. If that doesn't help, use VB's Sleep command (say 1 sec) before the kill command. (Include this line in your declarations for Sleep: Private Declare Sub Sleep Lib "kernel32.dll" (ByVal dwMilliseconds As Long)