The Lock method blocks other clients from modifying the variables stored in the Application object, ensuring that only one client at a time can alter or access the Application variables. If you do not call the Unlock method explicitly, the server unlocks the locked Application object when the .asp file ends or times out.
Application.Lock
<%
Application.Lock
Application("NumVisits") = Application("NumVisits") + 1
Application.Unlock
%>
This application page has been visited
<%= Application("NumVisits") %> times!
In the preceding example the Lock method prevents more than one client from accessing the variable NumVisits at a time. If the application had not been locked, two clients could try to increment the variable NumVisits simultaneously.