My grandson is staying with us, and recently built his own PC.
He did a nice job. it is a very decent rig.
Win 8.1 on I7 proc, with 8 Gb RAM, and I am fairly impressed.
He has only used the Windows firewall, and Windows Defender.
He has a habit, though of downloading new stuff from websites I tend to avoid, and he got bit really hard just recently.
He downloaded Spyware S&D and ran that, and it seemed to clean up most of the issues, but a couple of days later, it started acting up again.
I took a look at it last night. I also downloaded MBAR from here. Using both MBAR and S&D, I cleaned it up, but ran into a new problem.
The primary culprit appeared to be "Optimizer Pro" It took several runs of Search & Destroy and reboots before I actually cut the thing out.
Suddenly, the browsers could not get out to network target. I kept getting proxy errors.
Internet Options showed that the PC was configured to use a Proxy server which was set to the loopback.
I would unset the proxy and and the setting would not take.
So, to the registry.
I found the proxy settings in the Internet options section and cleaned that up. resetting the proxyenable and a couple of others to 0 and cleaning out the proxy addr, Save the registry, look in the internet options settings, and see that there was not proxy setting. As soon as I opened the browser, though. it failed with the proxy message. Back to internet options, Proxy was set, and I could not unset. Back to the registry, find the proxy settings, change, save, rinse, repeat.
after a few iterations of this, spending a lot of time looking for other clues, I started looking through the services, to see what else might be affecting network configuration.
I came across Bonjour. An Apple related service (He has an iPhone).
I stopped Bonjour. Went back to the registry and killed the Proxy, again.
This time it took.
So, lesson learned. Bonjour appears to have a hold on some of the configuration options. Should have stopped it to begin with.
I wanted to recreate the problem so I could get a better grasp of how all of that interrelated, but Grandson squawked at that. He says, "Go do that on your own computer!"
I guess I need to go buy a copy of Win 8.