Fix crashes and errors in production IIS sites.



High CPU

Memory leaks

Crash caused abnormal termination in the MvcApp application pool.

Determines root cause:

Crash caused by Stack overflow in ProfileHelper.ScavengeProfileCache().

Automatically diagnoses hard-to-catch crashes:

Stack overflow, unhandled exceptions, worker process timeouts.

Improve IIS website health by fixing crashes and critical errors

W3wp.exe crashes can cause instability and downtime for your IIS website. Worse yet, most APM tools don't report them because they crash along with your IIS worker process! Use LeanSentry to fix crashes and other important errors across your entire Windows Server, IIS, and ASP.NET stack.
  1. Identify code causing crashes in production.
  2. Safe for production with virtually zero overhead.
  3. Track Http.sys, IIS, ASP.NET, and application errors in one place.
"Our website has been running night and day better since the recent patches which were in a very large part thanks to LeanSentry. Cannot tell you how appreciative we are!"
Mike Boyle, IT Manager
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Track error impact across your entire Http.sys, IIS, and ASP.NET stack.

LeanSentry tracks IIS, ASP.NET, Http.sys errors
LeanSentry tracks all errors affecting your website health, and automatically groups them to show you the true combined impact of each error.

Get notified about critical errors and their causes.

LeanSentry critical error notification
LeanSentry detects and determines the cause of most critical IIS errors, including application pool failures, queue full, crashes, application initialization errors, and more. It then notifies you with the code-level cause of the error so you can fix it right away.

Prioritize and fix errors and crashes in your IIS website

Runs safely alongside your existing monitoring. Minimal overhead. Deploys in 5 minutes.

See the exact code causing your IIS worker process crashes.

Fix application code causing w3wp.exe crashes, including stack overflows, unhandled exceptions, and more.
LeanSentry crash diagnostics

Diagnose application pool failures and queueing down to the code triggering it.

LeanSentry automatically links application pool failures and IIS 503 Queue Full outages to the underlying causes, such as IIS thread pool exhaustion and CPU overload due to specific code.
LeanSentry IIS 503 service unavailable diagnostics
See how you can use LeanSentry Error diagnostics to fix critical website errors in our Fix IIS, ASP.NET, ASP and Http.sys errors guide.

Fix the most important errors affecting your IIS website health.

Fix the important errors that affect your customers, ignore the rest.

Get deeper insight without adding more overhead.

external non-blocking Runs side-by-side
with your APM
Low overhead monitoring, that can run side-by-side with your existing APM tools.
APM tools use profilers that intercept your application's execution. This can destabilize and slow down your apps.

LeanSentry uses external, non-intrusive monitoring that combines data from standard Windows logs including IIS logs, ETW traces, performance counters, and so on. This has almost zero overhead on your server and cannot crash or slow down your applications.

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