Thank you for bringing this problem to our attention. It seems that for some reason the toolbar is not correctly assigned to all editors after the AJAX postback. After replacing the RadAjaxPanel with standard asp:UpdatePanel the editors started to work as expected.
I have logged this issue into our database for further investigation and we will do our best to fix this issue for one of our upcoming releases.For the time being, I would suggest you to use asp:UpdatePanel instead of RadAjaxPanel when using ToolProviderID.
As a small token of gratitude I have updated your Telerik points.
the Telerik team
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