If you run PRTG Traffic Grapher as a service on your computer you may see Windows Event ID 7039 in your System Event log.
The message is:
A service process other than the one launched by the Service Control Manager connected when starting the PRTG Service service. The Service Control Manager launched process xxx and process yyy connected instead. Note that if this service is configured to start under a debugger, this behavior is expected.
The reason for this message is the license control and code tampering protection mechanism that we use in PRTG Traffic Grapher. Similar to a debugger it uses a second process to monitors the main process. This is the reason why Windows sees a different process ID when PRTG Traffic Grapher is started as a service.
So you can ignore Event ID 7039 for PRTG Traffic Grapher, it is expected behaviour.