I cannot get the value of the visibility of an element on the login page. I need to do this to change help text depending on login authentication being used on the portal.

document.getElementById('<%=pnlLoginContainer.ClientId%>').style.visibility fails and returns null.

I do not have the luxury of recompiling the core and getting id from server side so it must be client side javascript to get the visibility.

Any clues as to why the above returns null and not the visibility of the ctrl on the login page?

thanks