I've never used any Linux system before so please bear with me if I don't understand everything.

I have a Windows computer that's having virus/malware problems I haven't been able to fix. Someone suggested that I make a Knoppix Live CD and use f-prot to fix it.

I have Knoppix booted up just fine. But the instructions I was given say to go to "K Menu→KNOPPIX→Utilities→Install software". My menu doesn't have a utilities option.

I tried downloading the install files from the f-prot website and unpacked them. According to the readme, I should be able to copy the files into a folder and use the install file. But nothing happens when I execute the file.

I found this thread on a different forum which seems to be about the same issue but don't understand what they're talking about.

Any help would be greatly appreciated.

That link says that the old Knoppix dated around 2005 used to have the install script but is no longer used which is why you don't see it, nor me in my Knoppix.

Just to be sure of your method. I tried this with an older Knoppix and opened a terminal in Knoppix. I typed:
su

for a root prompt #
if you don't know, 'root' is the 'super-user' or admin in Linux and can do anything, normally you want to run just as a user.

the file you got is fp-linux-i686-ws.tar.gz yes?

this is unpacked into a /f-prot directory. Change to that directory and type:
./install-f-prot.pl

note the period '.' and slash '/'

I just hit 'Enter' at each dialog that followed and it installed. BUT there's a catch or two. That is an old version with old virus definitions and it wants to update them. Secondly if you haven't set up the network to go online in Knoppix then it will give a failed message only about that. You should be able to mount your windows partition and type:

fpscan -?? /xxxx where ?? are any options you want and /xxx is where windows is mounted.

Just a word about the mounting. Your hard disk will be /dev/hda or /dev/sda (depends knoppix version) and to check where windows is, in a terminal as root type:
fdisk /dev/sda

then type:
p

column on right will show 'ntfs' or 'fat32', note at left what it says like /dev/sda1. Now type:
q

to exit fdisk. Then type:
mkdir /mnt/win
then type:
mount /dev/sda1 /mnt/win

knoppix should know what type of filesystem it is. If a dialog appears here about wrong fs type then -t xxx (where xxx is the ntfs or fat32 for filesystem) needs to be put in after the 'mount'. You can find out about this by type:
man mount

page down till the '-t' part shows up. In Linux, man xxxx, where xxxx is a command usually brings up info about it.

If you don't have network sorted to get f-prot updates you could try a run on the windows partition. Look at the f-prot info for how to run a report only, that is _not_ try to fix any infections. Actually the option is '-report' and you can also get it listed as a text file you can look at later.

At this point I don't know about fixing a windows infection like this so a safe plan is to use knoppix to copy off personal data from the windows disk (mail, docs, pics etc etc) so if you do try to get f-prot to fix infections and windows gets barfed the you can re-install and your data is ok. As a last point, if f-prot, after updating it remember, says it repaired then you could boot back into windows and go online for an online scan at a respected site.