Hi Hassan,

Please note that the "ExcelDemo.xlsx" by default tries to connect to the "http://push.lightstreamer.com" port 80 (this is configurable by the cell A1).
Could you confirm that your machine has no problems reaching that URL?

Also, when you open the spreadsheet from your Excel should appear a window with the title: "Lightstreamer :: RTD Demo :: Excel"; in that window you should find some specific informations about any problem encountered during connection.

Regards,
Giuseppe