I believe I got it now. Peter, I find your joke better than the original one.

I am a little bit of types 1-5 ;) :) Just because the code works, it doesn't mean that it is good code.

Even scars from soldering iron burns? Software Zen: delete this;

Remove the semicolon after the binding expression document.getElementById("<%=txtOrderNo.ClientID%>;").value=""; it should be this document.getElementById("<%=txtOrderNo.ClientID%>").value=""; The former is adding the semicolon to the id which of course can't be found in the dom. I know the language. I've read a book. - _Madmatt

Hi.. The problem was due to permission levels when accessing from a virtual directory.I have added "Identity" tag in web.config.The problem was solved. Thanks for your suggestions.:thumbsup: