ASP.NET web application could restart or stop for numerous reasons. Most of the time, we would like that ASP.NET website is alive. To save resources, web server could restart or completely stop web application many times per day. Every time when this happens, website visitors could experience slow page loads, sessions could be lost, or even see error message in browser like "408 Request Timeout", "500 Internal Server Error", "503 Service Unavailable" etc. This tutorial explains what you can do when ASP.NET application restarts or stops execution.