How to convert multiple word documents from .doc to .docx?

I have many .doc documents located in many subfolders and I would like to covert them to .docx
I was opening each file and saving it but there are too many of them, so I thought there must be a better and a faster way. I found online some VBA code but none seem to work.
First VBA code:

Sub TranslateDocIntoDocx()
  Dim objWordApplication As New Word.Application
  Dim objWordDocument As Word.Document
  Dim strFile As String
  Dim strFolder As String

  strFolder = "H:\Vanhuspalvelut\Kotihoito\Tammelan_kotihoito\TURVALLISUUS\Pelastussuunnitelmaan_tuleva\TURVALLISUUS_SUUNNITELMA_2015"
  strFile = Dir(strFolder & "*.doc", vbNormal)
  
  While strFile <> ""
    With objWordApplication
      Set objWordDocument = .Documents.Open(FileName:=strFolder & strFile, AddToRecentFiles:=False, ReadOnly:=True, Visible:=False)
          
      With objWordDocument
        .SaveAs FileName:=strFolder & Replace(strFile, "doc", "docx"), FileFormat:=16
        .Close
      End With
    End With
    strFile = Dir()
  Wend

  Set objWordDocument = Nothing
  Set objWordApplication = Nothing
End Sub 

Second VBA code:

Sub ConvertBatchToDOCX()
    Dim sSourcePath As String
    Dim sTargetPath As String
    Dim sDocName As String
    Dim docCurDoc As Document
    Dim sNewDocName As String

    ' Looking in this path
    sSourcePath = "H:\Vanhuspalvelut\Kotihoito\Tammelan_kotihoito\TURVALLISUUS\Pelastussuunnitelmaan_tuleva\TURVALLISUUS_SUUNNITELMA_2015"
    sTargetPath = "H:\Vanhuspalvelut\Kotihoito\Tammelan_kotihoito\TURVALLISUUS\Pelastussuunnitelmaan_tuleva\TURVALLISUUS_SUUNNITELMA_2015"

   ' Look for first DOC file
    sDocName = Dir(sSourcePath & "*.doc")
    Do While sDocName <> ""
        ' Repeat as long as there are source files
        
        'Only work on files where right-most characters are ".doc"
        If Right(sDocName, 4) = ".doc" Then
            ' Open file
            Set docCurDoc = Documents.Open(FileName:=sSourcePath & sDocName)

            sNewDocName = Replace(sDocName, ".doc", ".docx")

            With docCurDoc
                .SaveAs FileName:=sTargetPath & sNewDocName, _
                  FileFormat:=wdFormatDocumentDefault
                .Close SaveChanges:=wdDoNotSaveChanges
            End With
        End If
        ' Get next source file name
        sDocName = Dir
    Loop
    MsgBox "Finished"
End Sub

Any help would be much appreciated!

>Solution :

In both routines you have the same small mistake: You miss a Backslash between the path and the filename. Your Dir-Command will see the following command and therefore doesn’t find anything:

Dir("H:\Vanhuspalvelut\Kotihoito\Tammelan_kotihoito\TURVALLISUUS\Pelastussuunnitelmaan_tuleva\TURVALLISUUS_SUUNNITELMA_2015*.doc", vbNormal

Either add the backslash at the end of the path definition:

strFolder = "H:\Vanhuspalvelut\Kotihoito\Tammelan_kotihoito\TURVALLISUUS\Pelastussuunnitelmaan_tuleva\TURVALLISUUS_SUUNNITELMA_2015\"

or put it into the Dir-command:

strFile = Dir(strFolder & "\*.doc", vbNormal)