Thanks for your reply, I didn't have a If not Page.IsPost which was preventing it from loading.

http://blogs.msdn.com/b/brianhartman/archive/2010/03/21/reports-never-stop-loading-with-vs-2010.aspx

Thanks for posting the code for this.

I've implemented exactly the same thing, but when I load the page with the ReportViewer control, the loading panel comes up but no...