Rootkits, if they are part of what’s going on, can be tough for regular antivirus software to track down. My daughter managed to get some bad stuff on the household computer once - despite not having admin access - and it was a misery to get it removed. This, despite running some antivirus or other (this was 10 years back, so I don’t recall what we had - possibly AVG).
I feel your pain there. My in-laws are in their 80s and MIL keeps trying to fall for scams. They have someone local who’s the “computer maven” who does a lot of stuff like setup and so on, which helps a lot - but we still get calls from them needing assistance.
The USB stick needs to be formatted with the correct file system. I don’t know whther that’s FAT32 or NTFS or …, but whatever it is, it needs to be the right one.
IIRC some cheapass USB sticks have custom drivers that assume they’re being used under Windows. Which of course won’t work if they’re being accessed by the raw PC’s BIOS/ UEFA system.
There is no way to know for certain from the packaging. Some such sticks might say “includes drivers for Windows & Mac” or some such. But the absence of such language is no guarantee.
Thought I was done with this. New Windows install, passwords changed, sites unblocked. Passwords now on paper, not stored on the computer.
But the bank is still investigating fraud. Mom did authorize the charge, so she can’t fill out that form that they sent. She has to request a fraud form. But how do we prove fraud? Would the description of that web page popping up that cannot be closed with a warning that the computer is at risk be enough? It doesn’t prove anything, how much discretion does the bank have?
A $299 charge is not going to break her, but she is going to want the money back on general principal and so am I. We’re not giving those nimrods $299!
Most modern USB drives are exFAT out of the packaging. Windows won’t even let you format a drive as FAT32 if it’s over 32 GB in size. (I tend to go with a 3rd party utility if it’s necessary to format a large drive as FAT32.)