Profiler conflicts

The .NET Common Language Runtime (CLR) only allows one profiler to access the profiling API of a process at any given time. If another profiler is installed on the system, the New Relic profiler will not instrument any applications. More information about the enviroment requirements for .NET CLR profiling can be found on MSDN.


To avoid a profiler conflict, fully remove the other profiler from the environment by following this procedure:

  1. Check for profiler conflicts.
  2. If necessary, compare the registry keys to the Process Explorer by using Microsoft PowerShell or the command line.

Exception: Follow the specific troubleshooting procedures for conflicts with Microsoft's System Center Operations Manager (SCOM).

Check for profiler conflicts

To see if there are any profiler conflicts:

  1. Run Process Explorer as administrator.
  2. Find your apps process by right clicking on it and selecting properties.
  3. Select the Environment tab.
  4. Verify that the New Relic CLSIDs are included in the w3wp.exe, service, or non-IIS app environment details:

    • COR_PROFILER={FF68FEB9-E58A-4B75-A2B8-90CE7D915A26}
    • COR_PROFILER={71DA0A04-7777-4EC6-9643-7D28B46A8A41}

Compare registry keys to Process Explorer

If the conflicting profiler has been disabled and there still is an issue, compare the registry keys to the Process Explorer to see which profiler is present: On the machine where you are experiencing this issue, check the WAS and W3SVC REG for IIS apps, or check your service/non-IIS app keys.

To check registry keys with this... Do this...

If using Microsoft PowerShell, execute the following commands:

(Get-Item -Path HKLM:\SYSTEM\CurrentControlSet\services\WAS).GetValue("Environment")
(Get-Item -Path HKLM:\SYSTEM\CurrentControlSet\services\W3SVC).GetValue("Environment")
Command line

If using cmd, do the following for either WAS and W3SVC REG or for your service/non-IIS app. Here is an example for an IIS application:

  1. On the command line, enter regedit.
  2. From the Registry Editor, select HKEY_LOCAL_MACHINE > SYSTEM > CurrentControlSet > Services.
  3. If applicable, select the WAS folder. From the WAS folder's list of registry keys, double-click Environment, and verify that New Relic's CLSIDs appear in the text box.
  4. If applicable, select the W3SVC folder. From the W3SVC folder's list of registry keys, double-click Environment, and verify that one of New Relic's CLSIDs appear in the text box.

Possible cause

Here are some commonly reported profiler conflicts. This is not an exhaustive list of .NET profilers, as any program that uses the .NET profiling API may cause conflicts with the New Relic .NET profiler.

Profiler name Profiler identifier
App Dynamics AppDynamics.AgentProfiler
Dynatrace DA7CFC47-3E35-4c-4e-B495-534F93B28683
Diagnostic Policy Service 555908d1-a6d7-4695-8e1e-26931d2012f4
IntelliTrace 2AA1AA98-2CAA-4FCF-86CE-EFA007737E83
Microsoft App Insights



SCOM APM AD5651A8-B5C8-46ca-A11B-E82AEC2B8E78

For more help

Join the discussion about .NET monitoring in the New Relic Online Technical Community! The Technical Community is a public platform to discuss and troubleshoot your New Relic toolset.

If you need additional help, get support at