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What To Do if Sensors Show a "Not Licensed" Message?



I'm getting a "Not licensed" or "Paused (exceeds license limitation of x sensors)" message for a number of sensors I added to the configuration. However, I have not reached the sensor limit for my license. How do I go about fixing this?

license prtg sensor

Created on Jan 25, 2010 9:57:28 PM by  Dirk Paessler [Founder Paessler AG] (11,025) 3 6

Last change on Jan 4, 2013 1:34:30 PM by  Daniel Zobel [Product Manager]

8 Replies

Accepted Answer



This article applies to PRTG Network Monitor 16.4.28 or later

Sensors Showing "Not Licensed" Message

PRTG Network Monitor is licensed on a 'per sensor' basis, meaning that the license does not limit monitoring to a number of devices. Due to this license mechanism it is possible that under circumstances PRTG Network Monitor will display a "Not Licensed" message. This article explains what to check and do if parts of your sensors in PRTG Network Monitor display a blue status icon and show 'Not Licensed'.

First of all, open Setup | License from the main menu bar in the PRTG web interface. The fields of interest are License Status and Licensed Edition.

Note: In older PRTG versions, you can find according information under "Setup | PRTG Status | System Status" or "System | PRTG Status | System Status". Look for the fields "Edition" and "Activation Status" in section "Licensing".

Freeware Edition (License key already in use)

If you find Freeware Edition (License key already in use) or a similar message in the edition field, then PRTG detected another instance of PRTG running with the same license key in your network (which is only allowed for unlimited licenses).

Deactivate the license on the second instance to revert it to a freeware edition or uninstall it after license deactivation. Then restart the PRTG services of your original PRTG installation.

Note: In older PRTG version you might have to enter a freeware or trial license key for the odd instance to stop running it as commercial edition. Use the PRTG Administration Tool (or PRTG Server Administrator) for this purpose.

Freeware Edition (Activation Grace Period Expired)

If you are running a commercial version and the program reports Freeware Edition (Activation Grace Period Expired), check under Setup | License from within PRTG. Please be aware that PRTG Network Monitor needs to be activated within 10 days (this is the 'Activation Grace Period') after the initial installation on a machine. As such, if you haven't activated, please try to do so using the automatic mechanism or, if this fails, use the manual activation option.

For details, see PRTG Manual: License Information.

Other Cases of 'Not Licensed' Sensors: Paused (exceeds license limitation of x sensors)

Most other cases with sensors showing a Not Licensed status are caused by exceeding the limit of licensed sensors. If the number of current used sensors exceeds the number of licensed sensors, all sensors above that limit will be paused automatically with the status Not licensed. In such an instance, please consider an upgrade to a higher edition of PRTG.

You can look up the number of used sensors under Setup | PRTG Status, section Database Objects, in the PRTG web interface and compare this number with your licensed edition.

Created on Jan 25, 2010 9:59:10 PM by  Dirk Paessler [Founder Paessler AG] (11,025) 3 6

Last change on Feb 8, 2024 12:15:38 PM by  Fruzsina Ébelle [Paessler Support]



What if I can't afford to upgrade the number of sensors right now? Can I just pause some of the other sensors? If I removed some of the other sensors I am not using why do these remain "Not licensed?

Created on Oct 14, 2010 11:23:13 PM



Your license allows to run the stated number of sensors at a time. For example, with a PRTG Network Monitor 500 license, you can run 500 sensors simultaneously. You can create more sensors than supported by your license, but these will be paused initially. You can then pause other (existing) sensors in order for the new sensors to start monitoring. Please note this only works with manually paused sensors.

Created on Oct 15, 2010 7:55:53 AM by  Daniel Zobel [Product Manager]

Last change on Jul 19, 2012 9:07:48 AM by  Daniel Zobel [Product Manager]



I have the sensors "Not Licensed" probem but none of above answers match. The bottom of PRTG welcome page reads "PRTG Network Monitor 500 license supports 500 sensors". I have 141 sensors running (green) and 23 paused with "not licensed". So it seems like if there was 141 sensors limit. Any help appreciated.

Created on Sep 7, 2012 9:22:45 AM



Please forward a screenshot of the "Setup -> PRTG status -> System status" page for analysis to [email protected]. Please refer to this knowledge base case.

Created on Sep 7, 2012 12:39:31 PM by  Patrick Hutter [Paessler Support] (7,225) 3 3



I don't seem to have "PRTG Status" in "Setup". What's there is: "Account Settings" and "Optional Downloads and Add-Ons"

Created on Sep 7, 2012 2:16:12 PM



Are you using a PRTG administrator account?

Created on Sep 7, 2012 3:02:51 PM by  Patrick Hutter [Paessler Support] (7,225) 3 3



Damn... I am not admin. And also I didn't know that other user have created 360 sensors before me so that only 140 was left. My apology for silly question and thank you for help!

Created on Sep 7, 2012 5:06:17 PM

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.