Option Explicit

Public Declare Function ShellExecute Lib "shell32.dll" Alias "ShellExecuteA" ( _
    ByVal hwnd As Long, ByVal lpOperation As String, ByVal lpFile As String, _
    ByVal lpParameters As String, ByVal lpDirectory As String, ByVal nShowCmd As Long) As Long
 
Public Function PrintPDF(xlHwnd As Long, FileName As String) As Boolean
  Dim X As Long
  
  On Error Resume Next
  X = ShellExecute(xlHwnd, "Print", FileName, 0&, 0&, 3)
  
  If Err.Number > 0 Then
    MsgBox Err.Number & ": " & Err.Description
    PrintPDF = False
  Else
      PrintPDF = True
  End If
  On Error GoTo 0
End Function

Sub PrintDocs()
  Dim aCC As ContentControl, sFile As String, sPath As String
  sPath = ActiveDocument.Path & Application.PathSeparator
  For Each aCC In ActiveDocument.ContentControls
    If aCC.Type = wdContentControlCheckBox Then
      If aCC.Checked Then
        sFile = sPath & aCC.Tag
        If Not PrintPDF(0, sFile) Then MsgBox "Printing failed: " & sFile
      End If
    End If
  Next aCC
End Sub