VBA code executes but only if I step thru it - excel

Question

I used some code from Close an opened PDF after opening it using FollowHyperlink to create the following code to open a pdf file and rename it. The code runs fine but only if I break execution at MsgBox "Break Here" and step into it with the F8 key. Any ideas on why it won't execute automatically?
Sub OpenPDF()
'Opens PDF Scaned file & saves it to another folder
'***ErrorHandler***
On Error Resume Next
'***Declare Objects****
Dim objectWMI As Object
Dim objectProcess As Object
Dim objectProcesses As Object
Dim Path As String
Dim MyDir As String
'***Opens a new workbook if there are no active workbooks***
'***There must be an active workbook for FollowHyperlink to function***
nowbs = Application.Workbooks.Count
If nowbs = 1 Then
Application.Workbooks.Add
Else
End If
'***Saves current Excel path
MyDir = CurDir
'***Sets path to Ricoh Scans
PDFDir = "S:\Ricoh Scans"
ChDir PDFDir
'***Gets filename for PDF scan
Path = Application.GetOpenFilename(filefilter:="PDF file (*.pdf), *.pdf")
'***Opens PDF file***
ActiveWorkbook.FollowHyperlink Path
'***Sets Excel as active application
AppActivate "Microsoft Excel"
'***Prompts for PO number****
MyPONum = InputBox("Enter PO Number", "PO Editor", "30500")
'***If user selects Cancel on inputbox then xl closes Acrobat and exits sub
If MyPONum = vbNullString Then
GoTo EndAll
Else
End If
'***Replaces scanned filename with inputbox filename
PathLen = Len(Path)
OldName = Mid(Path, 16, PathLen - 19)
NewName = "S:\Materials Management\Purchase Orders\PO " & MyPONum & ".pdf"
EndAll:
'***Set Objects***
Set objectWMI = GetObject("winmgmts://.")
Set objectProcesses = objectWMI.ExecQuery("SELECT * FROM Win32_Process WHERE Name = 'Acrobat.exe'") '< Change if you need be ** Was AcroRd32.exe**
'
'
'Code executes fine up to here but must Ctrl + Break at this line
'and F8 step thru balance of code or it will not work
'
'
MsgBox "Break Here"
'***Terminate all Open PDFs***
For Each objectProcess In objectProcesses
Call objectProcess.Terminate
Next
'***Clean Up***
Set objectProcesses = Nothing
Set objectWMI = Nothing
'***Renames scanned file and moves it to Materials Management folder***
Name Path As NewName
'***Resets current directory
ChDir MyDir
End Sub

Answer 1

Thanks to all for your input. I'm not a programmer and as I said I used code that had been posted elsewhere on this site. It was a timing issue and this edit works.
'***Terminate all Open PDFs***
For Each objectProcess In objectProcesses
objectProcess.Terminate
Next
'***Clean Up***
Set objectProcesses = Nothing
Set objectWMI = Nothing
'***************
Application.Wait (Now + TimeValue("00:00:02"))
'***Renames scanned file and moves it to Materials Management folder***
Name Path As NewName
'***Resets current directory
ChDir MyDir
End Sub