Issue
In the Power Monitoring Expert (PME) web application "Diagrams" tab, no diagrams can be viewed. The error message shows "[URL to access PME] redirected you too many times." The diagrams can however be seen in the Vista application without issue.

An error message can be seen in the windows event viewer, with ASP.NET as the source, and a message similar to "Could not authenticate Request Application path: C:\Program Files(x86)\Schneider Electric\Power Monitoring Expert\Applications\WebReach\. Process information: Process ID: 17820, Process name: w3wp.exe, Account name: NT AUTHORITY\NETWORK SERVICE.

Product line

Power Monitoring Expert 8.x
Power Monitoring Expert 9.x
Power Monitoring Expert 2020
Power Monitoring Expert 2021
Power Monitoring Expert 2022
Power Monitoring Expert 2023

Power Monitoring Expert 2024

Environment
Power Monitoring Expert (PME)

Internet Information Services (IIS)

Cause

At the time of installation, PME configures the Internet Information Services (IIS) manager to host the web application components, and PME leverages application pools https://product-help.schneider-electric.com/EcoStruxure/Power-Monitoring-Expert-2024/content/8_reference/planning/ref_iisapplicationpools.htm?Highlight=application pools. If PME is initially installed with SQL Server Authentication, The windows "NetworkService" is the default account that runs these application pools. Alternatively, if PME is installed with Windows Integrated Authentication, the Windows account used to access the PME databases is used. The specified error message is caused by that application pool account lacking privileges on the PME server, which prevents the worker process responsible for the diagrams from running.

Resolution

• To determine which application pool this message refers to, use the process ID listed in the error message.
• Open the IIS manager > expand the server name in the "connections" pane  > In the main view, select "worker processes"
  
• Identify which application pool uses the process ID previously found.
• In the connections pane, select "application pools"
• Right click on the previously identified application pool > select "Advanced settings"
• In the advanced settings, scroll to "process model" and select "Identity"
• In the application pool identity window, change the "built in account" from "NetworkService" to "LocalSystem" (native Windows account with the greatest privileges).
• Press OK.
• Refresh the PME web application, and the diagrams can be seen.
  • If not, run the command prompt as Administrator and run an "IISReset."

Released for: Schneider Electric Ireland