just try this ant let me know
//Delete User Log From Database on Browser Close
function DeleteUserLog()
{
// Check Browser Close [X] , Alt+F4 , File -> Close
if(window.event.clientX < 0 && window.event.clientY <0)
{
window.open("Removelogs.aspx", "OpenWindow_Close_Session",'left=12000,top=1200,width=10,height=1');
}
}
cheers, Abhijit