It is very difficult to determine the exact cause of the problem just from the provided information. Can you please elaborate some more on the issue.
If you are using ajax, try to disable it and see if the problem persists.
An alternate approach would be to enable your script debugging and confirm that no javascript errors are interfering.
It'd be best if you can provide us some more information on your project or send us the full markup of the page as well as the related code behind. Thus we will be able to further research on the problem and do our best to provide a proper solution.
Regards,
Eyup
the Telerik team
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