Option Explicit
Option Private Module
Sub ExportAllPDFs()
    Dim StrFile As String
    
    StrFile = Dir("C:\PdfFolder\*pdf")
    
    Do While Len(StrFile) > 0
        SavePDFAs StrFile, "jpeg"
        StrFile = Dir
    Loop
    
End Sub
Private Sub SavePDFAs(PDFPath As String, FileExtension As String)
    
    '---------------------------------------------------------------------------------------
    'Saves a PDF file as other format using Adobe Professional.
    
    'In order to use the macro you must enable the Acrobat library from VBA editor:
    'Go to Tools -> References -> Adobe Acrobat xx.0 Type Library, where xx depends
    'on your Acrobat Professional version (i.e. 9.0 or 10.0) you have installed to your PC.
    
    'Alternatively you can find it Tools -> References -> Browse and check for the path
    'C:\Program Files\Adobe\Acrobat xx.0\Acrobat\acrobat.tlb
    'where xx is your Acrobat version (i.e. 9.0 or 10.0 etc.).
    
    'By Christos Samaras
    'Date: 30/03/2013
    'http://www.myengineeringworld.net
    '---------------------------------------------------------------------------------------
    
    Dim objAcroApp      As Acrobat.AcroApp
    Dim objAcroAVDoc    As Acrobat.AcroAVDoc
    Dim objAcroPDDoc    As Acrobat.AcroPDDoc
    Dim objJSO          As Object
    Dim boResult        As Boolean
    Dim ExportFormat    As String
    Dim NewFilePath     As String
        
    'Initialize Acrobat by creating App object.
    Set objAcroApp = CreateObject("AcroExch.App")
    
    'Set AVDoc object.
    Set objAcroAVDoc = CreateObject("AcroExch.AVDoc")
    
    'Open the PDF file.
    boResult = objAcroAVDoc.Open(PDFPath, "")
        
    'Set the PDDoc object.
    Set objAcroPDDoc = objAcroAVDoc.GetPDDoc
    
    'Set the JS Object - Java Script Object.
    Set objJSO = objAcroPDDoc.GetJSObject
    
    'Check the type of conversion.
    Select Case LCase(FileExtension)
        Case "eps": ExportFormat = "com.adobe.acrobat.eps"
        Case "html", "htm": ExportFormat = "com.adobe.acrobat.html"
        Case "jpeg", "jpg", "jpe": ExportFormat = "com.adobe.acrobat.jpeg"
        Case "jpf", "jpx", "jp2", "j2k", "j2c", "jpc": ExportFormat = "com.adobe.acrobat.jp2k"
        Case "docx": ExportFormat = "com.adobe.acrobat.docx"
        Case "doc": ExportFormat = "com.adobe.acrobat.doc"
        Case "png": ExportFormat = "com.adobe.acrobat.png"
        Case "ps": ExportFormat = "com.adobe.acrobat.ps"
        Case "rft": ExportFormat = "com.adobe.acrobat.rft"
        Case "xlsx": ExportFormat = "com.adobe.acrobat.xlsx"
        Case "xls": ExportFormat = "com.adobe.acrobat.spreadsheet"
        Case "txt": ExportFormat = "com.adobe.acrobat.accesstext"
        Case "tiff", "tif": ExportFormat = "com.adobe.acrobat.tiff"
        Case "xml": ExportFormat = "com.adobe.acrobat.xml-1-00"
        Case Else: ExportFormat = "Wrong Input"
    End Select
    
    'Check if the format is correct and there are no errors.
    If ExportFormat <> "Wrong Input" And Err.Number = 0 Then
        
        'Format is correct and no errors.
        
        'Set the path of the new file. Note that Adobe instead of xls uses xml files.
        'That's why here the xls extension changes to xml.
        If LCase(FileExtension) <> "xls" Then
            NewFilePath = WorksheetFunction.Substitute(PDFPath, ".pdf", "." & LCase(FileExtension))
        Else
            NewFilePath = WorksheetFunction.Substitute(PDFPath, ".pdf", ".xml")
        End If
        
        'Save PDF file to the new format.
        boResult = objJSO.SaveAs(NewFilePath, ExportFormat)
        
        'Close the PDF file without saving the changes.
        boResult = objAcroAVDoc.Close(True)
        
        'Close the Acrobat application.
        boResult = objAcroApp.Exit
        
    Else
        
        'Something went wrong, so close the PDF file and the application.
        
        'Close the PDF file without saving the changes.
        boResult = objAcroAVDoc.Close(True)
        
        'Close the Acrobat application.
        boResult = objAcroApp.Exit
    End If
        
    'Release the objects.
    Set objAcroPDDoc = Nothing
    Set objAcroAVDoc = Nothing
    Set objAcroApp = Nothing
        
End Sub