VBA; Open PDF in existing PDF window (as a new tab) - vba

Question

I am trying to use VBA to open a PDF in an existing Adobe Acrobat window.
Currently, however, my code is opening the pdf in a separate Adobe window each time it is run.
End goal: VBA opens a PDF in an existing Adobe acrobat window in the form of a new PDF tab.
Here is my code:
Sub openPDF(sPath As String)
Dim primaryDoc As Object, PrimaryAVDoc As Object, appAdobe As Object ' Open Adobe instance
Dim zPath As String
Dim adobeDoc As Variant, PDFPageView As Variant
Set appAdobe = CreateObject("AcroExch.App")
' Create Adobe PDF object
Set primaryDoc = CreateObject("AcroExch.PDDoc")
Set PrimaryAVDoc = CreateObject("AcroExch.AVDoc")
If PrimaryAVDoc.Open(sPath, "") = True Then
PrimaryAVDoc.BringToFront
Call PrimaryAVDoc.Maximize(True)
Set PDFPageView = PrimaryAVDoc.GetAVPageView()
' Zoom (optional)
' Call PDFPageView.ZoomTo(2, 50)
End If
Set primaryDoc = Nothing
Set PrimaryAVDoc = Nothing
Set appAdobe = Nothing
End Sub

Answer 1

Whilst heavily used by programmable graphics applications, generally:-
This is a user application setting (depending on version user interface) it is unlikely to be externally program related (but see note below). Each user installation, just like in a browser, has user settings/preferences and this is thus a user run time option. I am not going to install every version or yours just to prove your user version does or does not have the required setting.
Many PDF viewers have legacy and Tabbed mode options (often addressable via DDE in Windows or Pipes in other systems) that may or may not be externally addressable for reuse windows. Those that are SyncTeX Aware usually have widest range of settings for external IDE calls. Adobe is SyncTeX Aware but offers fewer choices.
Here the upper quartiles setting is open as separate windows.
Lower view all files are now opened in tabs mode.