Hello,

we successfully created several Active Directory Replication Errors sensors which normally work fine. But every once in a while (sometimes several times a day, sometimes several times in a week) we receive the warning "Access denied (Exception of HRESULT: 0x80070005 (E_ACCESSDENIED))" on all of these sensors. Obviously no one changed any credentials or messed with any access permissions. We experience that error for several months now and couldn't get rid of it yet. We are currently using version 21.3.71.1416 of PRTG.

We would like to avoid these warnings since it is not only annoying but you might fail to see more important messages. Any help is greatly appreciated.

Cheers, Mirko

Article Comments

Hello,

these authentication issues can be hard to tackle. PRTG relies on Windows here.

Do you use a special account, created just for these PRTG sensors, to authenticate? That sometimes seems to help. It also eases the tracking of account issues in the Event Log.


Mar, 2022 - Permalink

We use a PRTG service account for using the sensors. I checked the windows logs, but couldn't find any problem there related to this. Generally it does work. It happens every once in a while and if it does, the error shows up for every single DC in our network.

Any hint where I should look more closely, maybe? Or is there another common way to check for replication errors apart from this specific sensor?


Mar, 2022 - Permalink

Hello Mirko,

there is no other sensor coming with PRTG doing that check. The alternative would be to script such sensor for yourself and use it via the Exe/Script Sensor.

As for debugging the authentication issue, there is little you can do from PRTG's side. PRTG uses the credentials you enter to perform the query. If Windows returns an error there, the issue would be somewhere there.

As for the user itself, please make sure that it has sufficient rights (domain administrator, as using other accounts can be complicated when querying Windows computers in a network.)


Mar, 2022 - Permalink

Hey Arne,

as this error only shows up intermittently, there is no problem with the credentials defined in PRTG. I used the Paessler WMI tester to check for problems but couldn't find any.

I found this page in the Paessler KB, and it seems that Paessler is well aware of this kind of problem but has no explanation for it (as stated in the linked article).
It well may be that the problem is within WMI itself but intermittent problems are always quite difficult to debug, especially if you are no expert.

I will continue finding an alternative way for checking AD replication errors.


Mar, 2022 - Permalink