If you are a business and get caught using an unlicensed PRTG instance, Paessler's legal team is aggressive. They will audit your network (common with German software companies) and demand back-payment for every sensor you ever used, plus penalty fees. This can reach tens of thousands of euros.

PRTG offers various license types to cater to different needs and budgets. Here are the most common license types:

: If you do not have a paid key, you can use the PRTG Freeware version, which provides up to 100 sensors for free with no expiration.

After entering the key, PRTG needs to "call home" to verify it. Setup | PRTG Status | Activation Status Start Activation Now Ensure your PRTG Core Server has internet access via (SSL) to reach the Paessler activation server. 4. What Happens if Your License Expires? PRTG offers both perpetual and subscription-based licenses. Subscription:

PRTG Network Monitor is a comprehensive network monitoring tool that provides real-time insights into network performance, availability, and security. It offers a wide range of features, including:

If the cost of a commercial PRTG key is prohibitive, consider these legitimate open-source alternatives (no keys required):