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Home > Success Center > Network Performance Monitor (NPM) > NPM - Knowledgebase Articles > Application Pool worker process is unresponsive

Application Pool worker process is unresponsive

Created by Michael Almadova, last modified by MindTouch on Jun 23, 2016

Views: 6,994 Votes: 0 Revisions: 6


The following error message appears in the Event Viewer:


Alert: Application Pool worker process is unresponsive
Source: SolarWinds Orion Application Pool
Last modified by: System
Last modified time: Alert description: A process serving application pool 'SolarWinds Orion Application Pool' suffered a fatal communication error with the Windows Process Activation Service. The process id was '9996'. The data field contains the error number.

Log Name: Application
Source: Application Error
Event ID: 1000
Task Category: (100)
Level: Error
Faulting application name: w3wp.exe, version: 7.5.7601.17514, time stamp: 0x4ce7a5f8
Faulting module name:, version: 4.0.30319.1026, time stamp: 0x53b50a71
Exception code: 0xc0000005
Fault offset: 0x002901c4
Faulting process id: 0x1cf0
Faulting application start time: 0x01d1521c34ae7c7d
Faulting application path: C:\Windows\SysWOW64\inetsrv\w3wp.exe
Faulting module path: C:\Windows\assembly\NativeImages_v4.0.30319_32\mscorlib\f014b1f34734c93956924e68c67ecb55\
Report Id: 2319617d-be17-11e5-a078-005056955de8


NPM 11.5.2


The Windows Process Activation Service causes IIS to crash, which generates the event for SolarWinds. 


  1. Check the IIS logs to see if IIS was restarted. 
  2. Check the system, windows, and application logs of the Event Viewer for WPA (Windows Process Activation) service causing IIS to crash. 
  3. If this is the case then, investigate the Windows issues to address IIS from crashing. 


Last modified