I have boiled this down to the most simple situation possible.
In a DropDownList_SelectedIndexChanged event, I put some text in a label. (VB.NET, ASPX)
It works testing on the Local Development Server, but not on the website.
AutoPostBack="True" should be OK (it makes the round trip in all cases)
Set the page <%@ OutputCache Duration="1" VaryByParam="none" %> duration as low as possible as per some research, etc. etc., etc.
Why does it work locally and not remotely?
Thanks in advance.