The problem is on my neighbour's Vista system, and seems to be "a.exe" and/or "W32.Ahlem.A@mm". Links, e.g in a Google search, are being diverted to different sites, and there are problems running and updating antivirus and spyware programs.
He had a McAfee trial system installed, which probably never got updated, also Spybot ditto. Trying to start the existing Spybot produced a message "Spybot is unable to run"; I uninstalled it and downloaded a new copy, but the installation fails when it tries to update files. I uninstalled McAfee and downloaded a new installation of AVG Free antivirus, which also fails to update.
Two preliminary questions, after reading your "Before you post" guidance:
1. The Erunt website says it is for NT/2000/XP - will it work with Vista, or is there another way to back up a Vista registry?
2. If I use a USB flash drive to carry HJT to his computer, and to carry logs back to mine for transmission, are there precautions I should take to prevent my system becoming infected?
3. Is there any point trying to update his newly installed Spybot with files from my (up-to-date) one? If so, which files? Note that my system is XP, his is Vista.