Bonjour Joris,
voici un exemple,
Sub Enregistre_csv()
Dim objShell As Object, objFolder As Object, oFolderItem As Object
Dim rep As String, Chemin As String
Set objShell = CreateObject("Shell.Application")
Set objFolder = objShell.BrowseForFolder(&H0&, "Choisir un répertoire", &H1&)
If objFolder Is Nothing Then Exit Sub
Set oFolderItem = objFolder.Items.Item
rep = oFolderItem.Path
Chemin = rep & "\" & "MonFichier.csv"
Sheets("OPTICOUPE").Copy
Application.DisplayAlerts = False
ActiveWorkbook.SaveAs Filename:=Chemin, FileFormat:=xlCSV, CreateBackup:=False
ActiveWorkbook.Close
Application.DisplayAlerts = True
End Sub