If you see the error message above, it means that you installed the latest version of the Framework ASP.NET1.1. Now ASP.NET 1.1 adds protection when you post HTML code and CuteEditor does that of course so here comes the error message, no harm just a warning.

To prevent this message from appearing again, you need to set validateRequest=false in the page header or add the following 2 lines to your web.config:

<!-- Allow posting html ...-->
<pages validateRequest="false"/>

Additional information can be found on the official ASP.NET website :

www.asp.net/faq/RequestValidation.aspx

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