My customer already purchase and deploy PRTG Network Monitor 1000 at the production network in the early time. The sensor usage for that license is low and found to be below 100 sensors is being used. Recently, the customer decided to purchase a new license on PRTG Network Monitor Enterprise 100 to replace the current 1000 sensor license once. One the replacement is proceeded, the originally license for PRTG Network Monitor 1000 will redeployed on another service network. Based on that requirement, can I know whether the PRTG Network Monitor allow the downgrade from 1000 sensor license to 100 sensor license once? Also, do the re-activitied from Internet or email if the originally 1000 sensor license has to deployed to another machines.

Thanks for your advice in advance.

Article Comments

I have a similar problem. We migrated PRTG to a different server. I followed all the instructions of the article in this knowledge base. The new server won't activate the license key and reverts to freeware even though PRTG is not active in the old server, so there is no other computer running PRTG at all. Why is this and how can I solve this?


Nov, 2012 - Permalink

Please open a Suppor Ticket or send an email to support@paessler.com refering to this thread. Please include your core and probe log files, as well as a screenshot of the "Setup -> PRTG status -> System status" page for analysis.


Nov, 2012 - Permalink

Any updates on this? The same thing is happening to us. We just finished migrating PRTG from Windows 2003 R2 32-bit to Windows 2008 R2 64-bit. The old PRTG server and services are off. Everything seemed to be fine, except that we got the following error....

ToDo: License Error Subject: License already in use

Your license key is already used by another computer in your network, but non-site-license keys may only be used on one PC. PRTG will now run as Freeware Edition.

PRTG Version PRTG Network Monitor 12.4.6.3230 x64

Any updates or info on how to resolve this? Or do we have to submit a support ticket to?


Nov, 2012 - Permalink

The last case might be a bit different than the ones above. Please have a look at What To Do if Sensors Show a "Not Licensed" Message?. If this does not show a resolution to your issue then, yes, please, open a ticket / forward a mail to support@paessler.com. These issues can have individual resolutions and require analysis of log files which, we presume, are not intended for public distribution.


Nov, 2012 - Permalink