Does your system have a router between your pc and the internet connection? Yes, router and powerline switch are connected Are you using the Windows firewall or a 3rd-party firewall? If the latter, which one? Windows firewall. More to the point: Does the system have any sort of "torrent" download app or any so-called "peer-to-peer filesharing" ? No torrent download. Does it have running any sort of instant messenger program? No IM programs Have you downloaded any sort of multi-media file (video or music or whatever) from an untrusted or unknown source? No music, video or pictures downloaded. And to make sure nothing is running I reboot and look in task manager. Thanks.