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How to get PRTG working after migration



I have just migrated PRTG from a working server to a new one, following the method on the PRTG knowledge base exactly. Once complete, I disconnected the original server from the network and connected the new one. All of the network was displayed, although only two groups of sensors were 'active', everything else remained greyed out. I disconnected the server from the network to check the settings and reconnected the original server. When this started up, all of the OTHER sensor groups were active (green), whilst the ones active on the new server were greyed out. I also recieved an email from PRTG after migration was complete saying:

This e-mail was sent by your network monitoring system "PRTG Network Monitor (WIN-8R0IO39MOTH)". There is something that you need to pay attention to:

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.

Please review all ToDos at

E-mail sent to: [email protected] E-mail sent at: 18/12/2013 13:31:13 E-mail sent by: PRTG Network Monitor (WIN-8R0IO39MOTH) (

Any help would be greatly, greatly appreciated.

fault migration prtg

Created on Dec 19, 2013 12:11:44 AM

1 Reply



Please refer to What To Do if Sensors Show a "Not Licensed" Message? for troubleshooting guidelines as regards this issue. If the information provided does not allow to fix the issue, please forward us an email to [email protected] including a support bundle, with reference to this thread.

Created on Dec 19, 2013 10:21:58 AM by  Patrick Hutter [Paessler Support] (7,225) 3 3

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.