gridview not repainting

Yo:

I am using the AsyncFileUpload to send a spreadsheet, which is then parsed and put into a database table. After that is done, I bind (or rebind) a GridView with the new data. But it doesn't display. I am injecting a javascript __doPostBack for the UpdatePanel. When this happens, I can see that during the Page_Load event that the GridView has the correct number of rows, but they still do not display.

Help!