This article applies to our products, such as PRTG Network Monitor and PRTG Enterprise Monitor.
If you receive a License not found error message in PRTG, it is most likely one of the following:
1. An error in the entered license key. It is possible there is a typo in the entered key. Double check the license key with the license document you received with your last purchase and try again. We recommend that you copy and paste the license key directly to avoid typos.
2. Your PRTG version is too old. Your license key might not be compatible with your installed PRTG version. In this case, you must update to the latest version. Follow the steps to update provided in the email that your license key came in.
3. Internet Connectivity Issues. If PRTG can't reach the activation server, it won’t validate your license. You may need to perform a manual activation if you're in an offline environment.
4. License may be already in use. If you've moved PRTG to a new system, the license might still be tied to the old one. In this case, deactivate the license on the old system (if possible), or contact Paessler support with your license and system ID.
For more information, see the PRTG Manual: Update from previous versions.
If you still need assistance, please reach out to our Customer Service team via helpdesk.paessler.com.
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