if you have a gridview in asp.net 2.0 page and u tried to bind it again after searching or any other action,u will get this error :
event RowEditing which wasn't handled ??!!
simply,one of the problem will cause this,that you have commands in your grid with the default name and you handle it on row command event handler.
by default,asp.net after bind the grid it generate the default event handlers like (Edit,Update,Delete).
Solution : just change default command name to anohter name,this problem will disappear.
Command name : Edit -->Change it to : EditCustomers
Hope this helps........ Enjoy with .net