It would be of great help if you can help us to know what would be the start date,from which this 60 days of the trail version will be counted?" - 60 day is the period of free support, which you receive with downloading the trial. It start from the download moment of RadControls for ASP.NET AJAX, RadEditor for MOSS, or any other ASP.NET AJAX product.
The control it self will never expire, however I as I explained on every couple or more loads a message explaining that this is a trial version will appear.
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