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Access denied in vbs custom sensor



In my installation I have many custom sensors, all warking OK against a Windows target (ps1, wmi) but the one created in vbs fails (access denied). If i log in (with admin credentials) to the server where prtg is installed, then this sensor works fine. If a close the session, the vbs sensor fails again with access denied. This script was working in prtg over windows 2008 r2 (probe was running under local system account). Now the problem is in prtg over windows 2012 r2 (probe under local system). With domain admin credentials, the scripts fails with other error

custom denied sensor vsb

Created on Jul 20, 2018 7:40:01 PM

1 Reply



Hi there,

Is there a particular reason why this script has to be in vbs while the other ones like Powershell are working properly? :)

You've mentioned that it works when you're logged in to the PRTG server. Does this mean the actual sensor is working then or did you mean that the script works when you start the script manually in command prompt? It's just strange, because the script is either executed in the default context of the probe (local system) or in the context of the Windows credentials of the parent device, see next paragraph.

Please check in the sensor's "Settings" tab if it's configured to use the security context of the Windows user from the parent device. Make sure you have entered valid credentials for the device in the device's "Settings" tab for Windows (try the same user you use when logging in to the PRTG server) and then try again.

Kind regards,


Created on Jul 23, 2018 10:34:46 AM by  Erhard Mikulik [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.