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When the App Visibility Agent for .NET is running then there should be two .dll files attached to the IIS worker process (w3wp.exe) within IIS.  To verify that these .dll files are bounded to the IIS worker process, perform the following steps:


Step 1) Download the Process Explorer utility at the following location:


and copy it to the server with the App Visibility Agent for .NET.


Step 2) Start the Process Explorer and click View -> Show Lower Pane


Step 3) Click View -> Lower Pane Window -> DLLs


Step 4) Look for the IIS worker process name called w3wp.exe and see if it is running.



An Internet Information Services (IIS) worker process is a windows process (w3wp.exe) which runs Web applications, and is responsible for handling requests sent to a Web Server for a specific application pool.  See for more information.  This w3wp.exe process only appears in Task Manager if any of the web sites is being accessed by web browsers. It is not a service at all.  So you can start w3wp.exe by going to the IIS home page like http://<IIS_hostname_here>.


Step 5) If w3wp.exe is present then click w3wp.exe and see if the following two .dll files in the lower pane that belongs to "BMC Software, Inc." are present:





See screen shot below:




If either one of these .dll files are not present then stop the App Visibility Agent for .NET and IIS (or stop the application pool or pools instead of IIS).  Then start the App Visibility Agent for .NET first and then start IIS (or start the application pool or pools).  Perform the above steps again to verify if the two .dll files are present.


If the ClrProfInstrumProbe.dll file is only missing then the App Visibility Agents for .NET will not able to find/map web applications on IIS.  We need to confirm if the worker process (w3wp.exe) has the correct value for the COR_PROFILER environment variable.  Below are the steps to check the COR_PROFILER environment variable:


Step 1) On the server with the App Visibility Agent for .NET, start the Process Explorer utility


Step 2) Look for the worker process (w3wp.exe)


Step 3) Right click on the w3wp.exe process and select Properties


Step 4) Click on the Environment tab and look for the following two environment variables:





The value for COR_ENABLE_PROFILING should be 1.

The value for COR_PROFILER should be {FF51CB90-1C9F-4b50-BA41-D48BDE9823B0}.


If the value for the COR_PROFILER environment variable is not {FF51CB90-1C9F-4b50-BA41-D48BDE9823B0} then it means that another APM monitoring program is interfering with the App Visibility Agent for .NET and that other product needs to be uninstalled.