snipped rest for brevity..... Ouch, now you guys are making my brain hurt. And I just got up this morning and am still on my first cup of coffee. The file copying, editing, etc I follow easily enough. As I've stated, I'm not a complete computer newbie. What's making my head hurt is all the different info and views about this licensing or product key thing. Probably it's just that I'm sort of dense, slow thinking, and a knuckle dragger pretending to be a homo sapien. I'm probably misunderstanding. But some of the info here sounds like methodology to circumvent having a LEGAL copy of Windows and using it. What makes me reasonably certain my impression is wrong is that in numerous posts to this Foum which I've read, the majority of posters appear to honest and intent upon not doing that. Ohhh, some may push the EULA thing by making hacks or changes not approved by MS. I'm not against that. Have done it myself with Win98. I just don't expect MS to provide customer support if I change their original stuff. And all I change is my own personal copy of the OS. (In the case of Win98, I haven't even tried to do such with XP as I know far too little about any of the NT based versions of Windows.) My conclusion? My head hurts. And I know I've gotta be misunderstanding something. I THOUGHT ... that the product key or COA, whichever as I'm not sure of the difference, was the equivalent of my "Proof of Purchase". A method to prove to MS that I did indeed buy and pay for one valid copy of a Windows OS, which I could freely use on ONE machine at a time. Thus, that has been the principle I've been going by. For each machine in my home, plus a few in my adult children's homes, I can produce one original CD, with the product key factory printed on it. I've got a CD storage cabinet with assorted and sundry original CDs in it. For various versions Windows, MS Office, etc. I do have backup copies of the CDs, with product key penciled in on a label. But if required can produce matching original. The backup is just that, a backup. Now, some of the machines in my home are running XP. And I've one copy for each of an original CD. Tho, not one for my wife's new machine, as it didn't come with a CD. Which caused my original question. How do I make a LEGAL backup of an install type CD, that I could legally use to rebuild her system if the HD crashed or something. Legal, as in she could reactivate HER copy of XP, go to MS's website without worrying for customer support, to get updates, etc. She could let em run their validation tool, with no worries, and so forth. Because she could demonstrate she has a valid license. Honestly gotten. I avoided asking any such question at any Warez or crackers group or forum, figured somebody on such would know, but also figured I might get questionable (as concerns legality) answers. I'm not particularly afraid of the boogey man, or MS trying to track me down, or anything. If I wanted to go an illegal route, I would. Simple as that. And figure my personal chances of getting away with it are pretty good. I'm not in the class with many of the folks whose posts I read here, but I do know a thing or 2. And have muddled my way thru reverse engineering a few times. (It's been a while, tho.) Even have all the basic tools and am not totally lost when dealing with assembly, C, C+, etc. And am quite aware one can find sites where one can download updates, fixes, upgrades, etc without ever pinging MS's sites. But I am a practical man. I'm not against MS, or any programmer, making an honest buck. (I am myself a programmer, but within a rather specialized field) Besides, if you're a legal owner of a liscense, you can reasonably expect at least some customer support and help. ie In my work I own legal liscence for a few specialty programs which I use daily. I quite reasonably expect that if one does not work as advertised I can call maker and complain. Have em fix problem, or tell me what I'm doing wrong, or provide some sort of work-around, etc. This is what I've been trying to maintain with MS. I don't use or like ALL of their apps. In some cases I think others do a particular chore better. And I'll use an app made by someone else instead of the MS equivalent. But my world, work world, is a DOS and Windows world. (Yes, DOS is still being used here and there. A number of things I work with still employ DOS, or a version of it. Sometimes embedded.) And most of the tools I use for automation work; dedicated controller setup, controller programming, GUI front-end creation, etc; are based upon the Windows platform. On the home front, I don't want my wife, for instance, to have to come to me for every nitpicking little thing as concerns her machine. I want her OS to be at least reasonably compliant and standard, so it'll run the things she uses without unnecessary hassles, I want her to be able to openly just click on "Updates" and get the latest changes, and I want her to be able to openly go to MS, her computer hardware maker, etc and ask for help when she has issues ... no problems ... because she's a legite customer. Sorry for being so long. But I'm trying to be clear. There are very good and valid reasons for being a LEGITIMATE customer. I wasn't asking for any illegal hacks or cracks. Not that I know that was what some of you were offering, I don't. I'm just confused about this product key/COA thing I'm guessing. I'm evidently not the least bit familiar with how it actually works. I was presuming it was something like a method we use for products we sell. Customer gets a unique "key", if yah want to call it that. Although other info is also required, such as customer name, address, ec. Copy of software CD is freely copiable. Make all the backups yah want. Want to put software on a different puter? Be our guest. But first wipe it off the original puter. The software does "phone home" so to speak. We don't care about customer's personal business. Or whether or not customer moves software once a year, once a month, or once a day. <Shrug> Customer's copy, do as yah like. But if TWO running copies with same identifier "phone home", we're gonna ask questions. Or if one copy "phones home" and has an identifier we have no record for. There are ways to defeat this, of course. I haven't done so, but could probably do it myself. But I won't. Want to run software on 2 machines at same time? Buy 2 copies. There is a discount for this. Also site licenses for running many copies. I'm guessing MS's system is not like this? Must be. My head is still hurting. But that's not at all unusual for us knuckle draggers. We're always behind the times and have trouble with new concepts. :-) Am I being told I can copy, for instance, my original ... it has the holograms and everything, Windows XP CD and use it to restore/reinstall my wife's system, as long as we enter that code on the sticker on the side of her new puter? Granting it's the same version of Windows? And everything will be legite? I appreciate everything everyone has said so far, and REALLY appreciate the patience you've had with this Neanderthal. The COA is your "Proof of Purchase" along with an original disc. However, each CD has a unique "Product Key" that uniquely identifies that copy of Windows, different from "CD Key" which is global. Windows Product Activation takes a snapshot of your hardware, and ties that with your "Product Key" and sends it to Microsoft to make sure that that "Product Key" is not installed on another machine at the same time. If you did not receive a CD with your Wife's PC, then the OEM has the CD on the hard drive on a recovery partition, or possibly somewhere under the Windows Directory... Now, with that being said, you should be able to tell that you cannot legally use one of your other CD's and install it on her machine, as the hardware is different, and therefore Microsoft would know it is installed on 2 machines at once. The CD Keys that the original poster was talking about are CD Keys designed for Manufacturers to use that are publicly available to get Windows installed on the machine. Who manufactured your wife's new machine? Perhaps one of us could help you locate the CD's files on the Hard Drive. One indicator that the OEM used a recovery partition is if you have a choice when booting to pick Windows XP or something else, and the other is if, when you look at the Hard Drive total capacity in Windows, it looks _way_ off from what the manufacturer said the total capacity would be (IE manufacturer says it is a 300GB drive and Windows reports it as a 250GB drive) If it says 279 GB, then that is fine because that is what my 300GB drive shows as and mine was bought at a retail outlet.