メモ。
VBAリファレンス(DIr)
Sub createFolder()
Dim targetDir As String: targetDir = "C:\test\"
Dim i As Integer: For i = 1 To Cells(Rows.Count, 1).End(xlUp).Row
Dim newDir As String: newDir = targetDir & Cells(i, 1).Value
If Dir(newDir, vbDirectory) = vbNullString Then MkDir newDir
Next i
Debug.Print ("end")
End Sub