title: Error This key is already associated with an element of this collection
body: <p>I am working on vba macros. I was trying to use a dictionary. But it is giving <code>error 457</code> with debugger pointing to <code>toprow.Add ActiveCell.value, val</code>. Can anyone please tell the issue? I even used <code>Cstr(activecell.value), Cstr(val)</code> as mentioned in one of the answer on similar issue.</p>
  
  <pre><code>Dim toprow As New Dictionary, Dictkey As Variant
  Dim val As String
  
  Range("A1").Activate 
  i = 0
  Do Until i = ColLen
      val = Chr(65 + i)
      toprow.Add ActiveCell.value, val
      i = i + 1
      ActiveCell.Offset(0, 1).Activate
  Loop
  </code></pre>