Just as with the AIDS virus, there is alot of bullshit concerning the
conditions under which a virus may infect your system. A virus can
only be caught by executing a program that has been infected with a
virus or by ATTEMPTING to boot up from an infected disk. You cannot
get a virus by merely LOOKING at an infected program or disk. A virus
can infect just about any executable file EXE COM OVL SYS DRV BIN and
the partition table and master boot record of floppies and hard disks.
Notice that above I said "attempting" to boot up from an infected
disk. Even if you attempt to boot up from A: and it tells you,
"Non-System disk" and then you boot from C: instead, the virus can
still be active if A: was infected. This is very important. It doesn't
have to be a succesful boot for the virus to get into memory. The
first thing it will probably do is infect C: drive. Then if you put a
new disk in A:, that will in turn be infected. That is why it is
important to keep a clean, write-protected floppy.
So, to sum it up:
þ You can catch a virus by executing an infected program, wether you
realize the program was run or not. This includes overlay files,
system drivers, EXE and COM files, etc.
þ You can catch a virus by ATTEMPTING to boot from an infected
floppy disk or hard disk, without regard as to whether that
attempt was succesful.
þ A cold boot will remove a virus from memory, a warm boot won't
necessarily do it. So press the button on your computer instead of
þ You CAN'T get a virus just from looking at an infected disk or
þ You CAN'T get a virus from a data file, unless it is actually an
executable and some other program renames it.
So in order to keep yourself in the clear, always check any new
program for viruses before running it, and never leave a disk in the
cd drive or usb when you boot upþ