I checked our records and noticed that you are first one to report this error for RadSpell. I searched for the error in Google
and found like you that the main reason for it is that the sever is busy or broken for some reason, which is not exactly related to RadSpell. It is also possible that the application is restarted for some reason.
Nevertheless, my suggestion is to try the recommendations in the above articles and try to resolve it. You can also check the server logs for any information about exceptions and errors.
the Telerik team
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