Sub Workbook_open()
Dim CsvFiles As String
Dim CsvPathFolder As String
Dim fso As Object
CsvPathFolder = GetDirectory("Select the folder, please")
Set fso = CreateObject("Scripting.FileSystemObject")
CsvFiles = Dir(CsvPathFolder & "\*.csv")
Do While CsvFiles <> ""
Application.Workbooks.Open
...
Loop
End Sub