title: Exception from HRESULT: 0x800A03EC when trying to add formula r1c1 while creating workbook
body: <p>I am creating an Excel file using C#.</p>
  
  <p>The end result should be:</p>
  
  <ol>
  <li><p>Excel workbook with 5 sheets</p></li>
  <li><p>1 sheet is generated using other 4 sheets.</p></li>
  <li><p>4 sheets are generated from database</p></li>
  <li><p>All the formulas should be added to sheet 1 just in case the user wants to add data manually to other 4 sheets </p></li>
  </ol>
  
  <p>I am stuck at:</p>
  
  <p>After I create all the 4 sheets, I am trying to add formulae to sheet 1.</p>
  
  <p>Formula Logic - Look for value of column A (all rows one by one) of sheet 1 (current) in sheet 2's column A, and get the value of column K of that row.</p>
  
  <p>I am trying to add the below VLOOKUP to the 12th row and will copy the formula to all rows.</p>
  
  <pre><code>oRng = worksheet.Range["J12"];
  oRng.FormulaR1C1 = "=IF(ISERROR(VLOOKUP(RC[-9],'Sheet2'!$A:$K,11,0)),'',VLOOKUP(RC[-9],'Sheet2'!$A:$K,11,0)";   
  </code></pre>
  
  <p>But I get the error:</p>
  
  <blockquote>
    <p>Exception from HRESULT: 0x800A03EC</p>
  </blockquote>