I don't think I completely understand. But I nearly always use the ShellExecute to call a handful of dos apps and the follow code has always worked for me:

Code:
Private Declare Function ShellExecute Lib "shell32.dll" Alias "ShellExecuteA" (ByVal hwnd As Long, ByVal lpOperation As String, ByVal lpFile As String, ByVal lpParameters As String, ByVal lpDirectory As String, ByVal nShowCmd As Long) As Long
Private Const SW_NORMAL = 1

Private Sub Command1_Click()
Dim sPrg as string
'Make sure you enter the full path.
sPrg="c:\marcbrkr.exe"
lret = ShellExecute(0&, "open", sPrg, vbNullString, 0&, SW_NORMAL)
End Sub
And if that doesn't work, you can always try the old standby

Code:
Private sub Command1_Click()

Dim x as long

x=Shell("c:\marcbrkr.exe",vbNormalFocus)

end sub
Good luck