Issue with ASP.net dropdownlist control

 I ran into a weird problem with ASP.net dropdown list
control and wondering if anybody has solution for
this. Here is the problem description,

I have a dropdown list control on my .aspx page along
with other controls and its "AutoPostback" property is
"True". I am trying to retrieve the data from SQL
Server database in code behind page
SelectedIndexChanged() method whenever a new item is
selected in the dropdown. It works fine every time
except if I don't expand the dropdown list control
until the page is completely rendered on client side. 

In other words, page is not rendered (just stays
empty) if I expand the dropdown while it is trying to
render or retrieve the data for previously selected
item. It looks like session is getting expired, I had
to refresh the browser in order to start over.

I am wondering if anybody ran into this problem,
please shed some light on this issue if anybody has
any ideas. Let me know if you know few more details.

Thanks in advance,
tsr


                
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