http://msmvps.com/blogs/shahed/archive/2008/06/26/asp-net-tips-making-custom-validators-work-in-partial-rendering-mode.aspxIntroduction There are many situations where we need to identify if partial rendering is supported in a page, especially when a control uses javascript, to get the control work in partial rendering mode, the script needs to be registered using a ScriptManagerenCommunityServer 2008.5 SP2 (Build: 40407.4157)