Helping people with computers... one answer at a time.

To 'legalize' your Windows XP Installation, simply install a legal copy over your old copy.

I bought a laptop with an illegal copy of Windows XP Professional. I want to remove this and get a new copy, as SP2 won't install. Can I reinstall over the current version? Or how do I remove the illegal copy? It doesn't appear in add remove programs.

Let me start by saying "good on you" for doing the right thing!

And doing the right thing is fairly easy.

I do want to point out that I don't think that Microsoft is restricting installations of SP2 to only legal installations just yet, though they have indicated that they plan to in the future. So, the illegal nature of your install may not be the issue there.

The short answer is to just install a legal copy of Windows XP on top of your old one. (Be sure to backup your data though, just in case.) The key will be to run Windows Activation once you're done so you register your legal copy with Microsoft. This will ensure that you're able to download and install future patches and updates. In addition, be sure to install SP2 right away.

If you were able to resolve the SP2 installation problem some other way, I'd also be tempted not to install the legal copy at all until I had to. Once you've actually purchased a copy you're technically legal, so unless you have other reasons to reinstall, you could just run with what you have. Eventually you will want to go ahead and reinstall; perhaps because Microsoft will begin enforcing legal updates only or many other reasons. In the interim, you'd be fine.

Oh, and as for Windows not showing up in it's own add/remove list... it can't! I suppose there could be an entry to "remove Windows" after which you'd be left with a machine with no operating system - which wouldn't make a lot of sense. I sure wouldn't put it there. Too many people would hit it by accident and be left with an unusable machine!

Article C2228 - November 20, 2004 « »

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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?

Justin Perkins
December 6, 2004 10:35 AM

I ran into a similar problem with 12 stations here that were purchased before I took over.

90% of the time, it is simpler to just run a repair instead of doing a clean install.

When you boot from the XP CD, once it loads, press enter to install windows, press F8 to accept the EULA and then press R to repair the OS. This will replace your bad SN with your new one.

Unfortunately, I can't find another way to change the key and activate.

R Skelton
April 17, 2005 2:16 PM

Well, I bought a computer with windows xp. Unfortunately for me the activation period is over and no one can log on. How do I get rid of this copy of xp? I can't log on to do it.

April 17, 2005 2:26 PM

Getting rid of Windows simply means installing somthing else (like Linux, or a different version of Windows).

July 11, 2005 3:39 AM

To 'go legal' with a reinstallation, is it enough to use an upgrade version rather than a full version?

July 11, 2005 8:17 PM

If you're upgrading from a legal version, yes. If it's the first version you've actually purchased, then technically you should be purchasing a full version.

August 28, 2005 6:53 AM

I also bought a desktop with a corporate edition of Windows XP Professional SP1 installed & won't allow me to update to SP2 saying I might have an illegal copy. I understand that you can just install a legal copy of Windows XP on top of the illegal one. Does that apply for OEM as well as retail?

August 29, 2005 10:00 PM

I believe it does, yes.

September 16, 2005 7:47 AM


When you have an Illegal Wds Pro Corp. installed you can't install a regular Pro version on that system.

tested multiple systems!

The most illegal installed version is Pro Corp, and there is a no go, when people go upgrade (downgrade) Pro Corp with the standard Home version.

February 9, 2006 4:30 AM

I recently found some software which retrieves your keycode and product id code from the computer, it also allows you to change those codes. Would it therefore be possible to convert an illegal copy to a legal one bye buying a properwindows xp pro and just changing your installed illegal version keys to the legal version ones without re installing? This would save all my drivers (sata raid etc etc) and other data....

May 28, 2006 11:35 PM

me and my cousin brought windows xp pro from a shop brand new and it was not fake but when i installed it it goes the serial key you have typed has been used loads of time (short words) so why???

Leo A. Notenboom
May 29, 2006 9:39 AM

Probably because that serial number had been pirated. Not neccesarily by that shop, but possibly. I would take it back and ask for another one. If that doesn't work, I'd call Microsoft for help.

July 17, 2006 2:09 PM

Will installing the legal version of windows XP over the illegal wipe my data for sure?

Leo Notenboom
July 17, 2006 5:55 PM

a) backup

b) a "repair" or "upgrade" install will not

c) assume that your data will be lost and backup anyway

July 19, 2006 2:25 AM

I had XP H.Edition and then installed XP Pro.
I can see my previous data in the PC.
They are not lost coz I can see the other Programs. But where are the other documents. PPTs, DOCs, PICs, etc.

August 2, 2006 7:14 PM

i have a ibm laptop and product key of Windows Xp pro, but i was losing my Windows XP Install CD.

How can i receive the Original Intallation of Windows Xp ?
Thank you very much

August 15, 2006 6:54 PM

i bough a brand new XD with home edtion sp2 , however, i lost my both serial key number( i just cant find them. Is there is any place i cen get the same number i case my computer brakes down and have to reinstall it. thank you for your time

Stu Maslow
September 20, 2006 11:04 AM

There are a number of programs that will allow you to change a Microsoft Product Key. You can even call Microsoft and they will walk you through it. I would recommend just chainging the PID. Once your PID is changed to your legal copy you will be able to install SP2 and be verified. If you have difficulty finding an answer I know I have the software in my archives.

charles greer
July 13, 2007 5:30 PM

Had my hp xp desktop since 2004 trying to add larger hard drive guess what microsoft will not let me use my legal windows and cannot finish changing hard drives can i sue them?

Leo A. Notenboom
July 15, 2007 3:46 PM

Hash: SHA1

If your hardware changes "too much" you may need to re-authorize your copy of
Windows because it looks like you've installed it on a different machine. If
the on-line auth doesn't work, then all you need to is call Microsoft. I've
actually heard good reports of that process working well. An occasional
annoyance, but working well.

Oh, and sure: anyone can sue anyone for any thing at any time.


Version: GnuPG v1.4.7 (MingW32)


Duncan Higgins
August 16, 2007 8:45 AM

I have, at present an illegal copy of Windows XP Pro which was put on my PC by a computer shop over the top of Windows XP Home edition which was a legal copy bought by me. Having read the above article, is it possible to install my Home Edition over the Pro edition. Will this work and make me legal again?

January 31, 2008 5:48 AM

hi.i ve3 bought a new pc a month ago. unfortunatelly vista its more than crap. i want to get xp on it but dont want to lose vista cos obvio. i ve payed for it . how can i install an xp on it without loosing vista??

February 13, 2008 1:41 PM

I bought a second hand PC with illegal windows XP Pro with SP2 installed. Can i buy XP Home and install that onto it with minimum effort? Backing up data is not a problem, im just worried about whether the PC will turn on again because i dont know how to install an OS.Any help appreciated!

mavel ramos
March 18, 2008 7:01 PM

I have the same problem like mark.I bought second hand pc with not genuine copy of windows XP pro.I want to install OS window XP Home but the software is already use in my other laptop is it still ok if I use again,install it to my second hand PC? can i install it by myself? how? can u tell me step by step......tnx

April 29, 2008 6:12 AM

I have, at present an illegal copy of Windows XP Pro which was put on my PC by my son over the top of Windows XP Home edition which was a legal copy bought by me. He was go to fit winlogon.exe unable to locate componet this application failed to stant shell 32.dll was not found, How can I remove the illegal copy of Windows XP Pro ?

May 22, 2008 12:40 AM

I have HP Compaq nx6120 Laptop with OS Win XP . the problem is that the recovery partition is formatted. No XP CD is provided by HP. I installed the pirated copy of Win XP on it. Can i make this as a leagal copy. I have the product Key of Win XP.

December 9, 2008 7:40 PM

i have 7 HP system recovery cd's win xp home edition. how do I find my serial # it did not come with it. is it on my cd's. Thank you Lee

It is not on the CD. It's on a sticker on the original box or computer. If the system is running, you can use Belarc Advisor to report the installation key use to install that system.
- Leo

February 15, 2009 7:51 AM

I have just bought a new computer and it came with an illegal copy of Windows XP Professional, thanks to this site I now know i can install my legal copy of Windows XP SP 2 Home Edition ( I just have to find out how to back up. My question though is that since i still have the illegal copy of Windows XP in my computer, is it the reason why I am unable to use Windows Live Messenger? It keeps saying something like ..' service is temporarily unavailable'...Thanks in advance if you could help me with this...

June 12, 2009 9:55 AM

Hi to All:)
I've searched solution for similar problem a while ago. Hope this helps to someone:

February 14, 2010 2:14 AM

No need of new instalation!

John Nawrocki
March 3, 2010 10:26 AM

I think you can register the copy of XP already installed on the PC. No need to reload the new copy. Just register with the new legal product key. Just so long as the two versions are the same (home, pro, etc...).

August 17, 2012 7:54 PM

I wonder if the comments made here apply to Win 7? I have the same problem in that I have purchased a used Dell Laptop which came with Win 7 Ultimate installed. Windows Update was enabled and all seemed fine until I tried to install MSE and was advised that installed Win 7 "May" be illegal. I contacted Microsoft for help/assistance and they confirmed that it is an illegal install. They also advised me that I needed to purchase a legal copy of O/S at approx AU$400. Dell gave the same answer but dearer still. I had used the Microsoft reporting system which stated that I "May" be eligible for a complimentary copy of the software in return for giving them the report and details of supplier etc. Note the "May" again! I gave them all the information I could, then they said, "Not eligible for complimentary copy". Gee am I surprised? Don't count on any assistance from them or the computer manufacturer. I could almost buy a new machine for the cost of the software. Could sure buy new one if added the cost of used machine to the software cost. I hope the machine will handle Win 8 when it is released. If not I will revert to Win XP as I have several full versions that have never been opened/used, or maybe I will have to finally learn to install and used Linux? I have been going to do this for several years. I am not sure if it is feasible on a well spec'd Dell. Any advice will be gratefully accepted. Thanks for an excellent service Leo. I read every issue your news letter and come to website often for more detail.

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