Failed to establish secure connection: Socket error 11002 - offline activation of license

Hello,

We are trying to install PRTG on a server on secure network (no internet connection allowed). We tried the offline activation and received error: Failed to establish secure connection: Socket error 11002 - offline activation of license.

If i change something in the key it says that the key is incorrect so it does know when it's correct and when it's not. what is the procedure to solve this issue. We are using the latest version that we downloaded from this site (i believe its version 18).

let me know if you need more information.

At the moment this is a free trial key for a customer that wants to start monitoring his network, if he likes the test he will most likely purchase a license, but first we need this to work..

offline-activation prtg socket-error-11002