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If you've lost your original product installation product key for Windows XP you may be out of luck. There are a few work-arounds you might try

Hi, Leo. I'm confused. I want to reinstall my Windows but I don't have the CD. Now I read all your posts about it. I downloaded a program to find my product key for the Windows I already have installed. I did find the product key but as I told, I don't have the installation CD - but I have an installation CD from another PC of mine. Now I tried to install Windows but when it asks for the key, it didn't find it suitable so I couldn't install. My PC runs Windows XP professional, SP3. The CD I have is for the same version. Is there any way to install Windows with an installation CD but with a product that was for my lost installation CD?

In this excerpt from Answercast #94 I look at the difficulties involved in trying to install Windows XP when the original media is lost.

Lost installation product key

Unfortunately, the answer is, "It depends." It sounds like, in your case, the answer is probably going to be "No."

Here's the problem: not all installation CDs are the same. The most obvious difference that we run across all the time is OEM CDs (in other words, the CD that the computer manufacturer may have given you with the computer) versus retail CDs (in other words, copies of Windows that you may have purchased at a retail outlet or online.)

Incompatible product keys

The key numbers, the actual product keys, for those two different versions are typically incompatible with each other. That actually extends to different manufacturers as well.

The product keys for say, an HP disc, might very well be different and not work on a disc that came from Dell - and they both probably won't work on a disc that came from a retail store. The only solution that I'm aware of is to use a product key that matches at least the type of disc that you have in your hand. If it's a retail disc, you need a retail key.

Now, in your case, technically this is illegal. But, using the product key for the disc you have on a second machine, probably feels at least ethical - because you have a product that you tried to install, you had installed on that machine for a long time and you simply lost the media.

Finding installation media

The other thing to try of course would be to contact the manufacturer of that computer. Now since we're talking Windows XP, it may too late. You may not be able to get any help from them but that's another venue to go down.

Another venue is to see if you can find the correct installation CD from a reseller or eBay. Again, that can be kind of iffy and you may not find what you need.

The final solution of course is to install and purchase a copy of the most recent version of Windows - Windows 7 or Windows 8 if your hardware is sufficiently powerful to run it.

Finally, the last solution, the "throw your hands up in the air and give up" solution is to actually install something like Ubuntu Linux, which you can download for free. There is no product key. It just works. It's a different operating system and it will take some getting used to. But depending on what you're doing and how use your computer, it's possible that it's a viable solution.

So, ultimately, it sounds like, for the situation that you're in; you are stuck in trying to do exactly what you want to do. Hopefully, one of the workarounds that I mentioned will at least get you further.

(Transcript lightly edited for readability.)

Next from Answercast 94- How long should I keep my backups?

Article C6309 - February 14, 2013 « »

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?

February 19, 2013 9:41 AM

Try using the key from the sticker on your PC.

John H
February 19, 2013 10:37 AM

You can use a program like Magic JellyBean Key Fnder to pull software keys from an operational computer.

I think Belarc will pull product keys.

I have heard of instances where the pulled keys from Microsoft may not work but I purchased several Ebay computers and was able to pull the product key and they worked.

Just like backing up your data, you need to backup your product keys. I keep mine in KeePass Pass word locker. I also photograph the stickers on the bottom of my laptops because they can wear off.

Leo, do not confuse ethical with legal especially in the US where large corporation cans influence legislation with political contributions.

February 19, 2013 11:10 AM

The first post "Use the product key on the sticker" is the correct answer, 'IF' it was in fact a legitimate install of XP Pro. If it was the 'original' OS, then the key in the machine is probably NOT the same as the registered key. I've seen this regularly, and my guess is the Mfgr uses a bulk key to install the OS on a manufacturing run, and labels each machine with it's unique registration. Using a basic instal CD for XP home edition, I've been able to recover (re-instal) the OS using the key assigned to the subject machine. There have been times I tried using the key found using a key finder that failed, and then using the tag key worked.
As to copyright issues, morally speaking, if your restoring the same OS system, the means shouldn't matter -damn the lawyers - I'll be one of twelve to vote to acquit!

Charlie Griffith
February 19, 2013 12:15 PM

Re using Ubuntu in lieu of a missing codes for Windows:
I simply wanted to try this Ubuntu system, "to learn something new"......

My own bad experience with kind, don't smirk:

....purchased their magazine, "Linux The Complete Manual" with the handy installation CD on the inside back cover, thinking that even I could manage to insert the disc into my trusty HP Pavilion 7000 laptop and have a good installation without using the dual boot method, thinking, "Why dual boot?", do I want Ubuntu or not?

That was my mistake.

Was able to get no further with that installed Ubuntu than my log-in page, that only started a circular repetitive in, repeat....So, found myself in the position of not being able to open Ubuntu, nor re-install from my original Win 7 disc with the applicable correct codes.

Staples now has the machine for a re-booting repair. I don't know what was the bug/matter with that Ubuntu CD, but it was the origin of trouble.

Charlie Griffith
February 19, 2013 12:26 PM

Product keys/codes on CD installation envelopes being inherently incompatible?.....I equate it with the alleged GM auto body style "Planned Obsolescence" of years ago.

It's merely a marketing ploy to sell more new installation CD's.....a ripoff. Try buying Win 7 installed on any new machines anywhere.....have the previously new Win 7 machines been re-booted? ....apparently so. Marketing-marketing-marketing. Phoooie.

February 19, 2013 12:36 PM

If that was originally an OEM installation, the product key that you saw with e.g. Key Finder is no good for a reinstallation with a CD from some other system.

You can, however, activate the installation of any media with the key which is on your COA sticker. On laptops, that is on the bottom of the laptop, on desktops, that is usually in the back of the case. That key is the valid key for your PC.

Marcus Potter
February 19, 2013 1:09 PM

Simple solution:

1) Don't give your product key during setup. Skip that step and accept the warning.
2) Download the Microsoft Windows key changer:
3) Click on Windows XP and download the key changer.
4) Type in your product key.
5) Activate (done automatically) but if this fails phone MS


{URL removed}

Mark J
February 19, 2013 3:26 PM

If the Windows installed on the computer is an OEM version, which is it in most cases, the number on the sticker is generally only good for that OEM version and not a retail version.

February 19, 2013 5:01 PM

I had the same issue except my laptop died completely. I used the same cd for an entirely different laptop which would'n't let me activate with the same OEM. I kept entering the code anyway and after the 3rd try it took.
I recommend creating a data cd of your installation cd and include all updates such as sp2 and 3 (for xp) in the future.

February 20, 2013 3:40 AM

Why doesn't anyone use their recovery CD-DVD's that they are required to make when the computer was just opened. If you did not make one, some manufacturers will mail one for $20 or so. If not, you no longer own Windows. Try to look for a used, but Not opened full version of XP. The Dell OEM will install, but in trial mode.

Just Me
February 20, 2013 12:27 PM

I do this all the time:

- Retail installation media requires a COA from the retail key subset

- Upgrade media requires a COA from the upgrade key subset

-VLK install requires the Mfg. supplied VLK installation media,
and it's supplied either in the recovery partition or the recovery media or both

- OEM System Builder media requires a COA from the OEM key subset,
in this case the Mfg. Supplied COA will work with OEM system builder media of the same version OS

the OEM supplied COA on the bottom / side of a PC is only valid when used in conjunction with an OEM system builder installation media
and will fail with invalid product key when used with any of the other installation media types

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