save pptx as pdf through excel - vba

Question

I am trying to convert all pptx files in a give path to pdf files.
my code:
Sub pptxtopdf()
Dim ppt As Object
Dim objFSO As Object
Dim objFolder As Object
Dim objFile As Object
Dim i As Integer
On Error Resume Next
Set ppt = GetObject(, "PowerPoint.Application")
If ppt Is Nothing Then
Set ppt = CreateObject("PowerPoint.Application")
End If
On Error GoTo 0
'Create an instance of the FileSystemObject
Set objFSO = CreateObject("Scripting.FileSystemObject")
'Get the folder object
Set objFolder = objFSO.GetFolder("P:\Operations\Data & Deliverables\Projects\Amica\presentation_workspace\1_ spring 2015\Presentations\Volvo")
i = 1
'loops through each file in the directory
For Each objFile In objFolder.Files
Set WDReport = ppt.Presentations.Open(objFile.Path)
Dim FileName2 As String
FileName2 = Replace(objFile.Path, "pptx", "pdf")
'WDReport.ExportAsFixedFormat FileName2, ppFixedFormatTypePDF
WDReport.SaveAs FileName2, ppSaveAsPDF
WDReport.Close
ppt.Quit
Set ppt = Nothing
Set WDReport = Nothing
i = i + 1
Next objFile
End Sub
error msg
Presentation.SaveAs : Invalid enumeration value.
Cannot see what I'm doing wrong?
same problem as here but the solution didnt work for me - Excel macro to save pptx as pdf; error with code

Answer 1

You are late binding PowerPoint.Application so its enumeration values are not exposed or available in the global VBA namespace.
As you have not added option explicit to warn you of undeclared variables your use of the undeclared ppSaveAsPDF causes no error but has no value.
Add:
const ppSaveAsPDF as long = 32
To the top of the module to provide the expected value to SaveAs.