Verifying data in Excel file

Gotcha... OK, then... rewriting your code a bit.  Note that I'm removing the ProcessData function as all that is doing is going through the driver an writnig to the log.  

function TestDriver()
{
  var Driver;
  
  // Creates the driver
  // If you connect to an Excel 2007 sheet, use the following method call:
  // Driver = DDT.ExcelDriver("C:\\MyFile.xlsx", "Sheet1", true);
  TestDriver = DDT.ExcelDriver("C:\\MyFile.xls", "Sheet1");
  BaseDriver = DDT.ExcelDriver("C:\\BaselineFile.xls", "Sheet1"):

  
  // Iterates through records
  RecNo = 0;
  while (!TestDriver.EOF() && !BaseDriver.EOF())
  {
    for (var i = 0, i < TestDriver.ColumnCount, i++) {
       if (TestDriver.Value(i) <> BaseDriver.Value(i)) {
       Log.Warning("Test file column " + TestDriver.ColumnName(i) + " does not match baseline")
       }
   }
    TestDriver.Next(); // Goes to the next record
    BaseDriver.Next();
  }
  
  // Closes the driver
  DDT.CloseDriver(TestDriver.Name);
  DDT.CloseDriver(BaseDriver.Name);
}

In side the for loop is where you do all your comparisons, etc.  I only included a very basic log warning but you could detail it out more with the values of test versus the values of baseline, etc.  Generally, this is what you're looking for... looping through BOTH files in parallel, one row at a time, comparing column values.