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WMI Logical Disk I/O Sensor Error - 2 is not free space



I have added the WMI Logical Disk I/O Sensor to a Server 2008 device and I am receiving the error:

"2 is not free space"

I have this sensor working on many other Windows Servers 2003, 2003 R2, 2012. This is the only 2008 Server I have so I'm not sure if it is a problem with the OS or PRTG?

logical-disk server-2008 wmi

Created on Jul 13, 2016 4:17:03 AM

Last change on Jul 14, 2016 10:59:42 AM by  Luciano Lingnau [Paessler]

7 Replies



Thank you for your KB-Post. Since you've mentioned that you're monitoring several servers/systems with this sensor without issues it's most likely a issue/corruption on the WMI.

Note: We have this sensor working successfully in our labs with Windows Server 2008 R2.

You can confirm the data returned by that host by issuing the following query with our WMI Tester:

SELECT * FROM Win32_PerfFormattedData_PerfDisk_LogicalDisk

What's the Output? Please share the result obtained in the tester.

Best Regards,
Luciano Lingnau [Paessler Support]

Created on Jul 14, 2016 11:03:04 AM by  Luciano Lingnau [Paessler]

Last change on Jul 14, 2016 11:04:00 AM by  Luciano Lingnau [Paessler]



I ran the WMITest tool with the above query and it returned the results correctly. I'm not sure how I could upload the entire result though, it is quite large.

Created on Jul 20, 2016 8:14:47 AM




Please open a support ticket so we will continue troubleshooting there.

Please send us in the ticket:

- the output of the WMI Tester,

- the screenshots of this sensor.

Please refer to this KB article in the ticket.

Thank you

Created on Jul 21, 2016 2:02:45 PM by  Isidora Jeremic [Paessler Support]




Same problem here :

  • Windows Server 2008 SP2 32bits French
  • PRTG

Same error:

"2 is not free space"

As for jcrookslakemac, this sensor works well on other Windows boxes (2003, 2008, 2012).



Created on Jul 27, 2016 6:59:54 AM

Last change on Jul 27, 2016 12:49:28 PM by  Luciano Lingnau [Paessler]



We're very sorry for this rather cryptic error message. As the sensor is still in beta-state, we do still have an issue with our error handling here. We're working on a bugfix for the problem and we'll also improved the error handling/messages for the sensor.

Edit: It seems this error message hides the original error message and without that original message it is impossible for us to find the problem.

Created on Jul 28, 2016 9:23:51 AM by  Johannes Herrmann [Paessler Support] (1,360) 2 2

Last change on Jul 28, 2016 10:26:18 AM by  Johannes Herrmann [Paessler Support] (1,360) 2 2




Sorry I have been away from the office and have not had a opportunity to create a ticket and send through the results. Do you still require me to do this?

Created on Aug 1, 2016 1:40:17 AM



Hello jcrookslakemac,
thank you for your reply.

As Johannes from our development team mentioned unfortunately the current error message is misleading, so at the moment any logs won't tell us much, this is a known issue and should be improved in future versions.

Please bear with us.

Created on Aug 1, 2016 7:50:24 AM by  Luciano Lingnau [Paessler]

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.