Windows Process Activation Service (WAS) encountered a failure when it started a worker process to serve the application pool
asp.net, iis, iis-7
Solution
If your application pool is running under a specific identity, an expired password could be the cause for your problem.
I had similar problems, see http://blog.janjonas.net/2012-07-14/iis_75-fix-application-pool-disabled-windows-process-activation-service-failure-worker-process-event-id-5059
Problem
IIS 7 Application Pool stops when browsing to http://localhost/ In Event Viewer -> System Log I see: Application pool ASP.NET v4.0 has been disabled. Windows Process Activation Service (WAS) encountered a failure when it started a worker process to serve the application pool. Are there other troubleshooting steps I can take to see a more detailed messages of why this is happening?