|"This was a particularly nasty virus that arrived as a parcel notification on email."|
This wasn't just a virus. This was a hacker attack that was successful. This form of attack is called social engineering. This needs to be taken seriously.
Your friend is not out of the woods yet. You may think the virus is gone but the hacker installed tools that are still there. And you will not be able to detect them.
Only known solution if backup your data files [not programs or any executable/com files] then reformat and reinstall the OS and programs from scratch. Then get your antivirus/antimalware/firewall programs installed, then selectively put the data back.
Understand the hacker is after personal info like identity info, banking info, other customers info, things of that sort that can be stolen and used to make the hacker money.
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