Links disabled

Hi all,

I have a web form which contains a frame, (a form containing a menu on the left and a  web form containing a datagrid on the right). Also there is a button (right side) which transforms the datagrid content in a CSV file and forces the user to download the file. The following is the code used to force a download:

  'strCadena contains the datagrid info separated by commas, as a CSV file
  Response.ContentType = "application/octet-stream"
  Response.AddHeader("content-disposition", "attachment;filename=Reporte_InfoRed.csv")
  Response.Write(strCadena)
  Response.End()

After the user saves the file, the links on the menu on the left side don't work and the buttons on the right side promt an error on the client side. It seems that the page gets an invalid state.

Does anybody know how can I solve it?

Thanks in advance.

God Bless.