Hi gajazz,
RK_Pihar_Group doesn't ring a bell. There is however, a Pihar family of rootkits.
Are you a Comcast XFINITY customer? As I understand from their forum
http://forums.comcast.com/t5/Security-and-Anti-Virus/Suspected-quot-bot-quot-Activity-email-from-Comcast/td-p/1397701, they have two Constant Guard™ services on offer.
If you have Constant Guard Protection Suite on your pc, you may be running Norton Security Suite. Since you're saying to be an avast user, that would mean two antivirus products on the same pc. This is advised against, since each antivirus gets in the way of the other. Please uninstall either one or the other; NSS of course, as this is an avast forum. Singular labs links to instructions and a tool for this
http://singularlabs.com/uninstallers/security-software/. And do read the instructions.
Next step would be to see if your pc is infected and remove the infection. Our volunteer malware removal specialists require you to gather some info on your pc, and attach the resulting logfiles to your next post in this thread. Here are instructions
http://forum.avast.com/index.php?topic=53253.0The other Constant Guard service runs on Comcast servers and seems to monitor your Internet traffic pattern. Hence they could determine your pc might be part of a botnet. I don't think a free cleanup of your pc is part of the XFINITY offering. So yes, Comcast would like you to pay for this
http://xfinity.comcast.net/constantguard/botassistance/dnsbot.
Comcast/XFINITY wouldn't scam their customers, so please do take steps to cleanup your computer. On this forum, advice is free; but due to different time zones it will take a little longer.
Best regards,