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Object reference not set to an instance of an object.



I am using a custom sensor using a Powershell script. I have copied this script on 2 different probes (1 W2K3 and 1 W2k8R2) on the EXEXML directory. This sensor is working on the monitored servers under the W2k8R2 probe, but not on the servers under de W2k3 probe. The error message is the same "Error reading response: Invalid XML (missing /prtg)", and in the Logs (Sensor) directory the error is like "Object reference not set to an instance of an object" When I run the script manually on the server all is fine, and the XML format of the return is correct.

The Execution policy is correctly set.

custom-sensor powershell prtg

Created on Apr 10, 2014 3:16:32 PM

1 Reply



Would it be possible to post the code from the Powershell script here for us to review? Also, please make sure that you have the correct credentials running the script and that the 32-bit Powershell is set up to allow remote signed scripts. Often, people enable this for the 64-bit Powershell and not the 32-bit.

Created on Apr 16, 2014 8:32:47 AM by  Greg Campion [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.