PDDoc.Save Adobe Acrobat method not working in Excel VBA

Question

Our office runs Arobat DC Pro and Excel 2016, we have been using the code below (scaled down version) in Excel VBA for years to save active Adobe PDF documents (that is, the open PDF doc that most recently had focus).

Since recently upgrading Arobat DC Pro to a newer version, the Acrobat PDDoc.Save method no longer works. It does not throw an error, it just doesn't save the active PDF.

I have had our IT dept. do an uninstall/reinstall of Acrobat PRO on a couple of computers but code still does not work.

Note, the Adobe Acrobat reference library is selected in VBA.

Any suggestions on how to fix?

Sub SaveActivePDF()

Dim AcroApp As Acrobat.CAcroApp
Dim PdDoc As Acrobat.CAcroPDDoc
Dim avdoc As Acrobat.CAcroAVDoc

Dim boolWasSaved As Boolean

Set AcroApp = CreateObject("AcroExch.App")
Set avdoc = AcroApp.GetActiveDoc
Set PdDoc = avdoc.GetPDDoc

DayTime = Format(Now, "yymmddhmmss")
Username = Environ("USERNAME")

PdfNewPath = "C:\Users\" & Username & "\Desktop\TEST PDF " & DayTime & ".pdf"

boolWasSaved = PDDoc.Save(PDSaveFull, PdfNewPath)   '<-- NOT WORKING 

If boolWasSaved = True Then
        MsgBox "PDF WAS SAVED!"
    Else: MsgBox "ERROR - PDF not saved"
End If

End Sub

Answer 1

For the record, access to the Acrobat library was blocked by sofware updates that changed default settings.

The issue was resolved as follows: Open any PDF > Edit > Preferences > Security (Enhanced) > ** UNCHECK ** check box "Enable Protected Mode at startup (Preview)" > exit all PDFs.