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    The 'ReferenceError: 'X' is not defined' error message appears when the Control.Enabled property is set to false

    Error Description

    The “ReferenceError: X is not defined” error message appears when you try to access a DevExpress ASP.NET control whose Enabled property is set to false.

    This error occurs because client scripts are not rendered for a control if its Enabled property is set to false. This means you cannot access the control on the client.

    Solution

    Use the ClientEnabled property to disable a control on the server and then make it available on the client.

    See Also

    The Difference Between the Enabled / Visible and ClientEnabled / ClientVisible Properties