Hi averwo,

Thanks for getting in touch.

Usually when this happens it's because the firewall is blocking those intermediate hops as they come through. I'm not sure why this would only happen on two of your PC's and not the third.

You might trying resetting the TCP/IP stack to see if that resolves the issue. If not, please submit a ticket from within the app (Help --> Email PingPlotter Support) so that we can take a closer look.