We seen some upgrades of Windows 10 to feature update 1909 experiencing issues.

The Remote Registry Service was disabled after update. Once the service was re-enabled and started, TopView could see monitored performance counters again - this is a requirement for remote viewing of performance counters.

If you are using Performance Counters to monitor TopView, please examine the state of the Remote Registry Service after Windows 10 updates to ensure it is enabled and set to run Automatically.