I ran in to a problem with ASP.NET 2.0 where postbacks werent working over the weekend. The problem as it seemed was that there was a corrupt copy of the webresource.axd file in my local cache. Cleaning the list of cache files that were associated with the target site and reloading the page solved the issue. Just a friendly tip for anyone having this problem Technorati : ASP.NET 2.0, Caching, Development, Postback...