title: RDLC report Error "Report item expressions can only refer to other report items within the same grouping scope or a containing grouping scope."
body: <p>I need to display some value on textbox which this value will receive from Tablix.</p>
  
  <p>But It's error this messesge</p>
  
  <pre><code>    The Value expression for the text box‘TextBoxName’ refers to the report item ‘NameOfTexboxInTablix’.
       Report item expressions can only refer to other report items within the same grouping scope or a containing grouping scope. 
        Letters in the names of report items must use the correct case.
  </code></pre>
  
  <p>In hidden tablix has a cell named "NameOfTexboxInTablix" which it use expression for getting value like this </p>
  
  <pre><code>    =Lookup(Fields!SEQ_NO.Value,"NO_2",Fields!PROCESS_CODE.Value, "PART_PROCESS")
  </code></pre>
  
  <p>And I have three Textbox (outside tablix) . Three textbox use for display
  a value from first row, second row and third rows of dataset.</p>
  
  <p>-Textbox1 will show "PROCESS_CODE" of the first row.</p>
  
  <p>-Textbox2  will show "PROCESS_CODE" of the second row.</p>
  
  <p>-Textbox3 will show "PROCESS_CODE" of  the third row.</p>
  
  <p>So I refer to a cell which it' is textbox in tablix. Textbox named <strong>"NameOfTexboxInTablix"</strong>. Textbox1,2 and 3 will refer by this expression </p>
  
  <pre><code>         =ReportItems!NameOfTexboxInTablix.Value
  </code></pre>
  
  <p>But It's error.</p>
  
  <p><strong>How to solved this problem without combind dataset?</strong></p>