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Domain\administrator bad password (kerberos pre-authentication failed)




We have PRTG in our global Active Directory, Server is in AUS, one PROBE (in DC in BOS site). Only PRTG software uses domain\administrator account in BOS server. We see monthly multiple "Bad password" event 4771 (kerberos pre-authentication failed) in BOS server trying to logon to BOS-DC, another multiple saying bad password while trying to logon to from BOS-DC to AUS-DC, number of event 4771 seems like matching the number of Windows servers (with Disk/Memory sensors)

After update version on 8/13, this become daily 7am EDT, or 9pm Australia time

Is there any way we can test to make sure that event 4771 come from PRTG system? -- stop the service without causing error alerts, then wait next morning to see if those event 4771 still come or not

Is there other way to check?

Thank you very much! Xiaolin

kerberos prtg wmi

Created on Aug 20, 2018 6:43:07 PM

1 Reply



Do you have the similar sensor detection enabled or any auto discoveries configured on these appliances? The former is located in the settings, at the very bottom in Advanced Network Analysis. Check the sensor management option in the device/group settings for any automatic discoveries that might occur here.

And yes, stopping the Probe Service should reveal if PRTG is at fault here.

Kind regards,
Stephan Linke, Tech Support Team

Created on Aug 21, 2018 11:27:26 AM by  Stephan Linke [Paessler Support]

Disclaimer: The information in the Paessler Knowledge Base comes without warranty of any kind. Use at your own risk. Before applying any instructions please exercise proper system administrator housekeeping. You must make sure that a proper backup of all your data is available.