I've recently downloaded the newest version to test against our solution. The following opens in my browser - can you explain that?
Excel excel1 = new Excel();
Cell cell = excel1.Worksheets[0].Cells["A1"];
cell.PutValue("First cell");
excel1.Save("testone", FileFormatType.Excel2003, SaveType.OpenInExcel, Response);
I use VS 2005 and IE6.0 on XP sp2