I am not sure what might be causing such behavior. Will it be possible to send the configuration of RadButton on your end or to isolate the issue in a fully runnable sample and send it for further inspection?
The following forum thread appears to be related to the same scenario: http://www.telerik.com/forums/enter-key-issue-with-radbutton-in-telerik-version-ui-for-asp-net-ajax-q1-2014
. If it is, let us continue our discussion on only one of the threads so that the information on the case is easier to track.
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