for folks that don’t have an installation CD for their system. But I’m still
confused … not every machine has this I386 directory, or if they do, it
doesn’t seem to have what you say it does. What is it, really? Should I have
it? What if I don’t? Do I want it?
Whoa … seems my answers around the I386 direectory have been generating
lots of additional questions as well. Let’s see if we can clarify they “I386
Let me start by answering a question you didn’t ask, because it’s related,
incredibly important, and the reason that I386 appears in so many of my
answers: In my opinion, you should never purchase a pre-installed operating
system without also getting the CD-ROM of the operating system that came
Clear enough? Now, let me tell you why I feel so strongly, and how it
relates to I386.
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If your machine has a “C:\I386” directory that contains several thousand
files, and that directory takes up over 600 megabytes of disk space then that
is the directory I’m talking about. It is most likely a copy of the Windows XP
Installation CD-ROM, or the I386 directory that is on that CD-ROM. If you find
an I386 directory elsewhere … say as a subdirectory buried somewhere else on
your system, then that is not what I’m discussing here.
Note that I said it’s just a copy of the installation CD-ROM. It’s not
created or installed automatically, it’s a copy of the original installation
CD-ROM made by whomever set up your machine, usually for two reasons:
- They didn’t give you an actual Windows XP Installation CD-ROM, so give you
the copy on the hard disk only instead
- It’s a shortcut to make it easier, later, if Windows asks for the
Those two are related.
As an example, when you add hardware to Windows – say you add a new printer
– Windows needs to get the appropriate files to support that new device. Since
it wasn’t connected to your computer when you set up Windows, those files were
not installed then; they need to be added now. Where do they come from? The
Windows Installation CD-ROM.
But what if you didn’t get a CD-ROM when you purchased your computer? By
having a copy of an installation CD-ROM in the C:\I386 directory, when
Windows asks for the original CD, you can tell it to look there instead. So
even though the manufacturer didn’t give you a physical CD-ROM, everything you
need is already on your hard disk, right there in C:\I386. When Windows needs
something from the original install CD, it can locate it there instead.
Can you see the flaw in this setup?
What happens if your hard disk crashes? What happens if you need to reformat
your hard disk? Everything is erased – including C:\I386. If you don’t have an
actual, physical, CD-ROM to reinstall from, you’re screwed – to put it
The second reason for C:\I386 existing is simple convenience. Even if you
have the CD-ROM, as you should, it’s often more convenient to keep a copy on
your hard drive. That way, instead of reaching for the CD-ROM each time Windows
needs something, you can just tell Windows to pick it up from C:\I386, already
on your hard disk. In fact, it’s such a convenience, and disk space is so
plentiful these days that copying the Windows XP CD-ROM to my hard disk is
often one of the first steps I take when I’m about to set up a new machine.
So what does all this mean? Well, remember that C:\I386 is just a copy of a
Windows Installation CD-ROM. Hence:
- You may not have C:\I386 on your machine. It’s certainly not required.
Hopefully you’ll have a Windows CD-ROM, should you need it.
- You may have C:\I386, but no Windows CD-ROM. I encourage you to a) backup
the C:\I386 directory you do have, and b) if you can, pester your computer
manufacturer for a physical CD-ROM.
- You may have both.
C:\I386 is not required for Windows to function. You can certainly copy it
elsewhere, perhaps to a different drive, or back it up to CD-ROM or DVD. (Even
though it’s a copy of a CD-ROM, some manufacturer’s appear to add to it, so
that the actual C:\I386 will no longer actually fit on a single CD-ROM).
But it is convenient.