1. Some other users had met this problem and when they update their windows, this issue is solved. I had also met this problem and solved it in the same way.
2. You can try the following code to generate the same problem without using Aspose.Excel.
FileStream fs1 = new FileStream("d:\\invoice.xls", FileMode.Open, FileAccess.Read);
byte[] data1 = new byte[fs1.Length];
fs1.Read(data1, 0, data1.Length);
this.Response.ContentType = "application/xls";
//In Aspose.Excel, if OpenInBrowser option specified, we use the following response header
Response.AddHeader( "content-disposition","inline; filename=book1.xls");
//In Aspose.Excel, if OpenInExcel option specified, we use the following response header
// Response.AddHeader( "content-disposition","attachment; filename=book1.xls");
Response.BinaryWrite(data1);
Response.End();
Other develpers met the same problem. Please check http://www.experts-exchange.com/Web/Browser_Issues/Q_20876347.html . They don't use Aspose.Excel.
3. If you don't find this problem from other sites to pull Excel files, I think they provide a url to download files, not directly send through Http Response object.
In your program, you can save the file to the disk on your server and provide a url link for your users to download. Then this problem will not occur.
4. You can also try to access your application through a machine which installed all windows patches.
5. I don't know which fix can solve this problem for I cannot find any announcement on microsoft web site. So it's better to install all windows patches.