I got the PC yesterday and it did turn ON but it took a long time to boot. This is an HP Pavilion 6. It has a second partition with a WIN10 OS. Luckily I did not have to reload the OS.
There was a DOS tab on the Start Menu. Opening it showed an ALARM with Trojan and a note for a bank.
The owner has already changed his password for all personal web sites.
Prior to this hack the owner, on my suggestion, purchased Webroot. That was running in the background along with MS Defender.

I updated and ran CCleaner. I also installed the free version of MalwareBytes. It found 10 PUP's. Also installed and ran Privazer, this found a lot of "stuff".
There were some drivers that needed updating and I took care of that.
I informed the owner that it might be a good idea to purchase MalwareBytes soon as a precaution. I will leave that up to him.
I am also suggesting he activate OneDrive as a backup.

I am confused that Defender and Webroot did not flag this virus.

Any suggestions that I might do before returning this PC to him?

Regards,
Dan Kahn