White screen after dropdownlist selection

[Chris Zopers]

Hello,

I have developed an ASP.NET page, with a dropdownlist and some
textboxes. When a selection is made in the dropdownlist, some data is
retrieved from a database and displayed in the textboxes.

To to this, I've written some code in the SelectedIndexChanged event of
the dropdownlist.

When a selection is made, it takes a few seconds for ASP.NET to retrieve
the data and display it. When I expand the dropdownlist again in those
few seconds, a blank white screen is displayed and I can't return to the
page anymore.

Does anyone know how to solve this problem?

Greetings,
Chris.