title: 'This field name is not known' error (Crystal Reports)
body: <p>Here is a strange problem I have run into.</p>
  
  <p>My record select formula is as follows, I have dumbed it down for purposes of this error:</p>
  
  <pre><code>reportDocument.RecordSelectionFormula = " {@ClientName} = 'Smith' "
  </code></pre>
  
  <p>If I copy this exact selection statement into Crystal it previews fine, but when run from .NET I get </p>
  
  <blockquote>
    <p>'This field name is not known'. </p>
  </blockquote>
  
  <p>The problem is occurring at the <code>@ClientName</code> formula field.</p>
  
  <p><code>@ClientName</code> simply contains:</p>
  
  <pre><code>formula = {aw_illust.CL1LNAM}
  </code></pre>
  
  <p>I can also set it to just a blank string (formula = "") and it still gives </p>
  
  <blockquote>
    <p>'This field name is not known.' </p>
  </blockquote>
  
  <p>Here is the strange part, if I bypass the formula and put the formula text straight into .NET everything works fine.</p>
  
  <pre><code>reportDocument.RecordSelectionFormula = " {aw_illust.CL1LNAM} = 'Smith' "
  </code></pre>
  
  <p>That is the same record selection, except with the '<code>@ClientName</code>' formula replaced with '<code>{aw_illust.CL1LNAM}</code>'. It just happens on this one report, I have many other Crystal Reports working with formulas referenced in .NET just fine. Any ideas? </p>