Unfortunately you cannot use the VB Shell function as it does not return a success or failure. Instead you have a couple of options that I know of:
1. Use the run method in the WshShell Object:
http://msdn.microsoft.com/en-us/library/d5fk67ky(VS.85).aspxAs in (using late binding):
Set WshShell = CreateObject("WScript.Shel
l")
Return = WshShell.Run(Cmd, 7, True)
Set WshShell = Nothing
2. Use the ShellExecute API directly. See here for a full discussion on the subject:
http://vbnet.mvps.org/code/intrinsic/sehyperlink.htm