I have tried to reproduce your scenario and the checkbox seems to be working properly. You can see the short video I recorded during my test here
. At the begging of the video I am checking the version of RadControls my current project is using. Could you confirm your RadContrls's version? Could you also share with us the browser you are having issues with and its version?
Your issue could be due to the server-side OnCheckedChanged event handler. Could you try removing it and run your page again? If the issue still persists could you try reproducing it with my VS example and then explain what kind of changes have you done?
Regarding your question about the response time - forum threads are community content and do not have a guaranteed response from Telerik. Nevertheless, we keep an eye on the forums and respond to the questions when that is possible. Generally speaking, above 95% of the questions in the forums get answered. If you need to receive an answer related to our products quickly, you should open a support ticket (its response time is 24h). Note that you should have an active subscription in order to open a ticket.
the Telerik team
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