Hi,

I have been throught a lot of trouble making work telerik controls with a proxy. I'm using asp.net webform on IIS with .net 4.5 and Telerik  2020.3.1021.45

I recently added a reverse proxy (ARR) to IIS to make my website work with the blue/green pattern to get a 0 downtime deployment. So I get a webfarm that redirect to the live website with the reverseproxy. Every things work great except telerik controls.

I get many javascript exception that make me think that the telerik webressource doesnt seems to get through the proxy :  

• ASP.NET Ajax client-side framework failed to load
• 'Sys' is undefined
• “Telerik.Web.UI” is undefined

I tried to change many stuff but without sucess :

• Suppress radcompression from webconfig
• modified the <httpHandlers> and <handlers> for WebResource.axd. Changed the type to Telerik.Web.UI.WebResourceSession since I use a webfarm with shared session state.
  • How to integrate RadControls for ASP.NET AJAX in a WebFarm o (telerik.com)
• Added a <location> section to the application configuration file to allow access to Telerik.Web.UI.WebResource.axd 
  • ASP.NET Ajax client-side framework failed to load in UI for ASP.NET AJAX | Telerik Forums
• added EnableScriptCombine="false"  to telerik:RadScriptManager
  • work for all simple controls (dropdownlist) but failed for datagrid and other ajax control)

• change webfarm caching in IIS to "Include query string"

  • Reverse Proxy (ARR) and ScriptResource.axd Issue in UI for ASP.NET AJAX | Telerik Forums

I don't know what to check next. Thank you for your advices/ideas...

JF