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Line Number 1, Column 1:

I want to download a Excel file. I wrote the data in a html table format and appending to the response. The code is following :

Response.Buffer = false;
Response.Expires = 0;
Response.Clear();
Response.ContentType = "application/vnd.ms-excel";
Response.AddHeader("Content-Disposition", "attachment; filename=" + FileName);
Response.Write(str);
Response.End();