When trying to uninstall the PI Notifications Service I get the following error: 'Failed to uninstall performance counters (-2147024891)'.
After the error occurs the uninstall aborts leaving the PI Notifications Service in place as is, however the service will no longer start.
The PI Notifications Service log file contains the following messages to indicate why the service failed to start:
PI Notification Service on this machine xxx is not registered to run on the AF Server. The PI Notification registered is on machine ''
Service configuration element not found at path: \Configuration\OSIsoft\PIANO\Notifications\Service