Set FSO = CreateObject("Scripting.FileSystemObject")
 
File = AskFile(FSO.GetAbsolutePathName(".\"), ".pptx")
 
Do Until FSO.FileExists(File)
	Msgbox "El archivo no existe: " & File, 16
	File = AskFile(FSO.GetAbsolutePathName(".\"), ".pptx")
Loop
 
WScript.CreateObject("WScript.Shell").Run """" & File & """", 1, False
WScript.Quit(0)
 
Function AskFile(Directory, FileExt)
 
	Do Until Not FileName = ""
		FileName = InputBox("Escribe el nombre del archivo (Ej: 001)", "PowerPoint")
	Loop
 
	If Not Len(Filename) > 5 _
	   Or Not (LCase(Right(Filename, 5)) = LCase(FileExt)) Then
 
		FileName = FileName & FileExt
 
	End If
 
	AskFile = Directory & "\" & FileName ' FullPath
 
End Function