title: External table is not in the expected format thrown only in certain situations
body: <p>I am trying to open an xlsx file and I get the External table is not in the expected format only when I open from a certain area of my app. So it works just fine if I call it from 1 area, but then I do the same thing from a different part of the app, calling the same code block, and it throws that exception. Same code block. Same excel file.</p>
  
  <pre><code>string connectionString = "Provider="+ GetProvider(fileName) +"; data source=" + fileName + "; " + GetExtendedProperties(fileName);
  
                  using (var connection = new OleDbConnection(connectionString))
                  {
                      connection.Open();
  
                      using (DataTable schemaTable = connection.GetOleDbSchemaTable(OleDbSchemaGuid.Tables,
                                                                                    new object[] { null, null, null, "TABLE" }))
                      {
                          if (schemaTable != null &amp;&amp; schemaTable.Rows != null)
                          {
                              List&lt;string&gt; validTables = schemaTable.Rows.OfType&lt;DataRow&gt;().Select(row =&gt; (string)row["TABLE_NAME"]).ToList();
  
                              validTables.ForEach(table =&gt;
                              {
                                  if (table.Contains('$'))
                                  {
                                      results.WorkSheets.Add(table.Trim('\'', '$'));
                                  }
                                  else
                                  {
                                      results.NamedRanges.Add(table);
                                  }
                              });
                          }
                      }
                  }
  </code></pre>
  
  <p>My connection string:</p>
  
  <p>Provider=Microsoft.ACE.OLEDB.12.0; data source=C:\moses\BLANKTest\Table.xlsx; Extended Properties="Excel 12.0 Xml";</p>
  
  <p>Also tried the connection string taking out the "Xml" at the end. No luck.</p>
  
  <p>Not sure what is going on here.</p>