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The I386 folder usually contains a copy of the files used to install Windows in the first place. You can often use it to reinstall Windows.

If I burn the I386 folder onto a CD will it be the same as having Windows XP on a CD? Will that just allow me to delete the folder, and if I choose to restart will the CD be fully applicable?


An actual Windows Setup CD is different in some subtle ways and at least one not-to-subtle way: you can boot from it to perform an install. A CD copy of your I386 folder won't do that.

But there are some ways to use the I386 folder to reinstall your system.

First I have to throw out a big fat caveat: I can't guarantee that any of this will work. The problem is that while it's common for the I386 folder to be and do what I'm going to talk about, there's actually no standard that says it must. As always, make sure you're totally backed up - or be ready to lose everything on your machine - before you attempt anything as system-altering as a reinstall.

As I've discussed before, many computer manufacturers include a folder on your primary hard drive: C:\I386. This folder typically contains a copy of the I386 folder that's on your installation CD - if your computer came with one. That folder contains all of the files that are used when you install Windows XP, and when Windows later decides it needs files that weren't originally installed. That's actually one reason that the folder is copied to your hard drive: Windows won't have to ask for the CD, but rather simply copy what it needs from the C:\I386 folder.

You can move the I386 folder to another location or even to another machine on your local network if you like, to free up the space on your hard disk.

"ANY installation copy of Windows is actually not worth much without the product activation key."

And of course, you can burn it to CD.

If it fits.

And right there is the first of several the problems many folks face.

My I386 folder is 850Meg, much too large to burn onto a CD. Either the original installation CD used some form of additional compression to reduce that size, or my manufacturer added files to the folder. I'm actually not sure which, but the result is the same: the folder's too big to fit on a CD, and I wouldn't know what to safely remove to make it fit.

If you have the ability, you can of course burn it to a DVD. Or copy it to an external hard drive. Or copy it to a file server on your local network.

But what then?

Well, first make sure you have, or save, your product key. ANY installation copy of Windows is actually not worth much without the product activation key. You can retrieve the product key from your running installation or from the sticker on your original CD or perhaps the PC itself.

Next, in the I386 folder, look for one of these three programs:

  • setup.exe

  • winnt32.exe

  • winnt.exe

Those are all different versions of the Windows setup program. If you have them, or especially if you have all three, you have hope. (If you do have all, I'd try them in the order listed.)

Now, as I said, you can't boot from the CD or DVD you've created. But if you can come up with another way to boot your machine, you may be able to use your copy of the I386 folder to re-setup Windows.

The 'trick', such as it is, is simply to boot your machine in such a way that you can run the setup program. You may even be able to do it directly in the C:\I386 folder, though you won't be able to do a true "reformat" and reinstall since the reformat would erase the I386 folder you're attempting to install from. (And remember I did say to backup, and that includes backing up that I386 folder as well, just in case.) If not, you might need to boot from a floppy or a different CD, and from there access wherever your I386 folder has been placed.

Particularly if you're able to place and access the I386 folder from some location other than your machine's primary hard drive, you should be able to install Windows as if you had the original CD.

Now a few more caveats:

  • Your I386 folder will represent an image of your original installation - before any patches. Your first job after installing should be to a) ensure the firewall is turned on before you connect to the network, and then b) visit Windows Update. Repeatedly. Until you're completely up to date.

  • Manufacturers might have mucked about with the contents of I386. They might have added software or tools or they might remove some. There's no telling.

  • You might have mucked about with the contents of I386. I know, it's not likely, but it is an unprotected folder on your hard drive, and particularly if you don't know what it is it's easy to accidentally delete portions or make inadvertent changes.

The bottom line is that the best installation source for Windows is an official product CD or DVD. But if for some reason you don't have one, but you do have a legal product key from your existing installation, the I386 folder might well be a helpful fallback position.

Article C3243 - December 20, 2007 « »

Leo Leo A. Notenboom has been playing with computers since he was required to take a programming class in 1976. An 18 year career as a programmer at Microsoft soon followed. After "retiring" in 2001, Leo started Ask Leo! in 2003 as a place for answers to common computer and technical questions. More about Leo.

Not what you needed?

Wayne Feese
December 21, 2007 6:47 PM

Leo, when I first installed XP I copied the Xp disk to my hard drive to C:\XP. This has saved me a coulple of times. A set of boot disk is also helpful if you cannot dind your original Cd

Terry Hollett
December 22, 2007 5:42 AM

Just a few notes:

setup.exe - Only works within Windows. I formated my hard drive when I first installed WinXP, booted from a floppy disk, only to discover the setup program would not run from DOS. I had to reinstall WinME, set everything up again, go online to find out how to install for a clean hard drive (my computer at the time couldn't boot of a CDROM either)

winnt32.exe - This is for a MSDOS or command prompt within Windows.

winnt.exe - If you can't boot of a CD, and formated your hard drive, hopefully you can boot of a floppy, this is the one to start the install.

Terry Hollett

allan frahm
December 22, 2007 5:48 PM

much trouble trying to access links on 12/22-click
on a link and an add comes up for many different
items and cannot print your replies in many
cases it is blocked.

Edward Lockhart
December 22, 2007 10:31 PM

It is far easier and more efficient to make an image of your OS partition with Acronis or Drive Image and to restore your drive with this back-up image when necessary.This is a quite fast and reliable method of restore and also protects and preserves settings,connections,and any installed programs.Further benefits can also be gained by saving an image of a "virgin install" and using it to "start fresh" if need be,as this is much faster than normal OS installs.I highly recommend use of these imaging methods for ALL computer owners and users.Making images of other partitions and data is also a very useful tool for complete backup and safety of your computer.You can save these image files on DVD,an external drive,on other drives or all for multiple backup with ease.Imaging as such will save you many hours and bring your systems back in a flash...Be sure to make an Bootable Recovery Disk and keep this in safe storage with your image disks.

xp man
January 14, 2009 7:15 PM

you may won to look at this page it is step by step to help you create an boot able windows cd it works very well only takes about 30min

February 17, 2010 8:59 PM

everything very nice but. I purchesed referbished computer with legal key for windows xp proffesional. I do not have the disk. I have a legal copy of window xp home edition. I installed that home edition version and copied the I386 folder from another computer running on windows xp proffesional. I run winnt32.exe and the installation (upgrade) process started nicely as I expected. I enterd the key from the case of the newly purchesed referbished computer and .. great the installation is going. However at certain moment the setup goe to the required automatic restart. At this moment everithng stops. The machine can not restart. Black screen with flashing cursor. I wait few hours and nothing happend. After manual restart I got option to start windows home edition or go to setup of the xp professional. I chose the second option and it took mi immedietly to the black screen and flashing cursor. Choosing xp home just start the home version of widos xp from which I can start the whole proces again. Any sugestion how to get windows xp professional on my computer?

Thank you

June 1, 2011 4:12 PM

I successfully installed xp home sp3 on a machine using the i386 folder which I had managed to recover from a failing hard drive. I installed PowerISO on a different machine, this is what I used to produce the bootable install CD. I used an xp home sp3 image and that's it!
1. Open xp home sp3 image in poweriso (right click xp image and "open with...poweriso")
You should see the entire contents of the image in poweriso.
3. Delete the i386 folder.
4. Copy over the i386 folder I want to use into poweriso.
5. Burn disk at low speed.

Result:- one bootable xp home sp3 disk.
No need for Product Key.
I was able to perform a fresh install of xp using this disk. It is important you use the correct version of the xp image. If I had used an xp home sp2 image then the install would have failed because the pc I was trying to repair originally came with xp home sp3.

Tinker Dude
June 30, 2011 11:50 AM

I found C:/I386 on my Compaq V6000 notebook. I wanted a fresh XP install minus the bloatware included on the recovery discs and partition.
I copied C:/I386 to the desktop, then, copied the 4 oembios files located in C:/Windows into the I386 folder on the desktop, used search to locate them.
Opened the I386 folder on desktop with Nlite, Windows XP MCE 2005 was detected, selected cancel when asked to browse for components location, I won't be using media centre.

sliptreamed SP3, intergrated drivers that had been backed up with Double Driver freeware program.
Ran a freeware key-finder, inserted generic OEM in unattended setup, removed media centre option in Nlite.
Works a treat, hope this helps someone.

Tinker Dude
June 30, 2011 12:01 PM

My previous post.........create a a desktop folder to put C:/I386 into, or you might end with files all over the desktop.

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