Invalid postback or callback argument

[Matt MacDonald]

Hi all,
I know this question has been posted all over the place, but it doesn't
look like there are any definative answers, especially for the scenario I am
using.

I have a site with a masterpage. In the header of the masterpage, there is
a text box with a search button. This button adds the value of the text box
to the session state and then forwards the user to the search page. The
search page inserts this value into the text attribute of another text box
and runs a site search against the MS index service based on the text of
this second text box on the webserver and populate a datagrid with a
template column with the results. This is, I think, a fairly standard site
search scenario. When doing one or two searches from the header, everything
functions fine. After the third or fourth time though, I get the famous
"Invalid postback or callback argument" error message. I have tried turning
eventvalidation off in the web.config, although I would rather keep it on.
I also tried manually registering the buttons for eventvalidation in the
render methods of the pages. Nothing has seemed to work. Any help would be
appreciated.

I am using ASP.NET 2.0 with VS2005.

Thanks,
Matt