Debug this error: Multiple controls with same ID 'ctl00$ctl00$ctl34' were found
<p>For literally years, my website has very intermittently thrown the following exception:</p>

<blockquote>
  <p>Multiple controls with the same ID
  'ctl00$ctl00$ctl34' were found. Trace
  requires that controls have unique
  IDs.</p>
  
  <p>at System.Web.TraceContext.AddNewControl(String
  id, String parentId, String type,
  Int32 viewStateSize, Int32
  controlStateSize)</p>
  
  <p>at System.Web.UI.Control.BuildProfileTree(String
  parentId, Boolean calcViewState) </p>
  
  <p>.... etc (entire stack trace is within System.Web namespace)</p>
  
  <p>at
  System.Web.HttpApplication.ExecuteStep(IExecutionStep
  step, Boolean&amp; completedSynchronously)</p>
</blockquote>

<p>Sometimes a user will go to a page and this exception will be thrown - it happens on different pages and different control ids show up. Often, reloading the page will work. Other times, the exception will persist for a few refreshes before fixing itself.</p>

<p>Now I know that this error usually occurs when you are adding dynamic controls to a page and you accidently use the same ID within the one naming container, so I understand the meaning of the error.</p>

<p>But on my site, I am not adding dynamic controls. At least not that I know of.</p>

<p>I am running third-party components like Umbraco, Telerik and Peter Blum, and they are almost certainly adding control dynamically to the control tree at times, but, like I said, this error has been around for years, across major versions of all of these modules.</p>

<p>The intermittent nature of the exception suggests some sort of multi-threaded timing issue or use of a random number somewhere. Who knows... I can't find the cause of it in <em>my</em> code.</p>

<p>So my question is - how could I go about debugging this issue, given that the entire stack trace is within the .NET framework?</p>
