title: Excel Interop Load Template into Existing Workbook
body: <p>How can I load the sheets from a template into the existing Excel workbook (if there is no existing workbook then create a blank one first).</p>
  
  <p>I have tried</p>
  
  <pre><code>Excel.Application.Workbooks.Open("path");
  </code></pre>
  
  <p>this works but every time it creates a new Excel session as it's creating a new workbook. I have not been able to find anything through Google on how to load the data as a new sheet into the existing book.</p>