Stubborn problem with processes failing

Hey everyone, new here. I’ve been using Comodo for a long time and never had any issues on my own computer, but now I’m helping out a friend and his problems are baffling me as I’ve never experienced them myself.

His antivirus(Trend) expired at some point, and he didn’t recognize it, so it ran unprotected for a while it seems. His computer began freezing up to the point where I could not even bring the task manager up(Failure to display security and shutdown options error), and any given one of his files were giving me server execution errors when trying to open them.

I found a temporary solution with resetting winsock via the command prompt(which I had to do from Safe Mode because I could not even bring it up in normal mode), which seemed to fix things for a little bit, but the source of the problem seemed to stem from the computer connecting to the internet. It worked find without the wireless on, but as soon as I would turn it on, the computer would start to hang after 10 minutes or so, and the aforementioned problems would rear their ugly heads again.

I have done a system restore, installed Comodo AV and FW for him, and have run a scan from Malwarebytes, but nothing seems to be working after I turn his WiFi back on, which leads me to believe something(a virus maybe) is trying to connect to the internet, since everything works great when the Wi-Fi is off.

Also, I can’t run Comodo in Safe Mode for some reason, and it gives me the Diagnostics error, which doesn’t fix anything.

Any suggestions?

I would try scanning with a bootable disk. For advice as to how to do that please see this section of my article about How to Clean An Infected Computer.

Let me know how that goes, and what it finds, and we can continue from there.