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Object reference not set to an instance of an object.



I am using a HTTP XML/REST Value sensor against a json feed. Every so often something in the json response will cause PRTG to display the error "Object reference not set to an instance of an object." instead of grabbing the requested value.

The feed can be found at http://blogs.mprnews.org/newscut/?json=1&include=id&count=1 I am grabbing the count_total value.

I ran the url through http://jsonlint.com/ and it says that the json is valid.

json prtg rest xml

Created on Dec 30, 2013 5:33:41 PM

3 Replies

Accepted Answer




please exchange your XMLValue.exe in

C:\Program Files (x86)\PRTG Network Monitor\Sensor System

for the one you can download here


and then please try again.

Created on Jan 3, 2014 8:13:25 AM by  Aurelio Lombardi [Paessler Support]



I deployed the executable. Everything seems to be working as expected.

Created on Jan 3, 2014 5:21:25 PM



When we updated PRTG, now to version The XML file was updated and this error returned. I deployed this executable again to the server and the error cleared up.

Am I going to have to do this every time there is a PRTG release?


Created on Feb 22, 2014 12:33:34 AM

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