Can you confirm that all the requests executed by the page are successful? If there are requests which are not successful they could prevent control's scripts and styles from loading. If that is the case you can try
- Toggling the state of the CDN(turning it on/off)
- Clearing the cache of the browser/ASP server on which you are running the page.
- Use Fiddler or FireBug to see which requests are failing and why. You can also examine briefly Web Resources Troubleshooting help article and use the provided solutions, in case similar issues are present.
Can you also confirm whether the issue is browser specific (if so which is the browser and its version) or it occurs in most major browsers like FireFox, Chrome and Safari?
If the above steps are not helpful could you please try to send us a fully runnable sample with reproduction steps of the issue, so that we can make an investigation locally?
If you want to get updates on new releases, tips and tricks and sneak peeks at our product labs directly from the developers working on the RadControls for ASP.NET AJAX, subscribe to the blog feed