# Question about Windows licensing **URL:** \ **Category:** Factual Questions\ **Created:** [September 14, 2011, 12:24pm UTC](https://boards.straightdope.com/t/question-about-windows-licensing/596277 "2011-09-14T12:24:46Z")\ **Posts on this page:** 15\ **Page:** 1
**Author:** ![Mean\_Mr.Mustard](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mean_mr.mustard/32/3865_2.png) [@Mean\_Mr.Mustard](https://boards.straightdope.com/u/Mean_Mr.Mustard)\ **Post date:** [September 14, 2011, 12:24pm UTC](https://boards.straightdope.com/t/question-about-windows-licensing/596277/1 "2011-09-14T12:24:46Z")
I offered to take a look at a friend’s jacked-up laptop; as it turns out, it seems to be virus-infested. It won’t even let me download an anti-virus program. Since she has nothing of importance on it, I’d like to do a clean install. But she has none of the discs that came with the unit. I do have a Windows 7 full install disc, but I know I’ve used it 3 or 4 times already. I don’t really want to ‘give away’ my remaining activations. So, if I understand correctly, you are allowed x number of installs with one install disc. Is this correct? If so, what is the magic number. And finally, how painful is it to obtain a sort of extension (or, is this possible?). Thanks, mmm ---
**Author:** ![Mangetout](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mangetout/32/19_2.png) [@Mangetout](https://boards.straightdope.com/u/Mangetout)\ **Post date:** [September 14, 2011, 12:32pm UTC](https://boards.straightdope.com/t/question-about-windows-licensing/596277/2 "2011-09-14T12:32:21Z")
I don’t think it works like that - the install media are mass-produced, and not writable so the installer shouldn’t ‘know’ how many times it has been used. I think all you need to do is find the existing product key, using [this](http://pcsupport.about.com/od/productkeysactivation/ht/windows-7-key.htm)method, or similar, then install using that. (It’s possible that the product key of the existing installation might not be appropriate for the install media you have - if, for example, it was originally an OEM licence or some such) ---
**Author:** ![lazybratsche](https://avatars.discourse-cdn.com/v4/letter/l/ba8739/32.png) [@lazybratsche](https://boards.straightdope.com/u/lazybratsche)\ **Post date:** [September 14, 2011, 12:33pm UTC](https://boards.straightdope.com/t/question-about-windows-licensing/596277/3 "2011-09-14T12:33:41Z")
You’re in luck! There’s no limit on the number of times you can use a particular install CD, and they’re all interchangeable as long as you use the right version\*. There is a limit on the number of times a specific _product key_ can be activated. But you can use your install disk, and your friend’s product key, which is usually on a sticker on the bottom of the laptop. FWIW, if you run up against the “too many activations of a given key” limit, all you have to do is call their number and tell some very nice people that you’re not installing it on multiple machines. \*ETA: If you’ve got a Home Premium install disk, and the laptop has a Home Premium license sticker on the bottom, you should be set. I could be wrong but I don’t think there’s a substantial difference between OEM and retail copies. ---
**Author:** ![MercuryP](https://avatars.discourse-cdn.com/v4/letter/m/96bed5/32.png) [@MercuryP](https://boards.straightdope.com/u/MercuryP)\ **Post date:** [September 14, 2011, 12:57pm UTC](https://boards.straightdope.com/t/question-about-windows-licensing/596277/4 "2011-09-14T12:57:48Z")
I can confirm lazybratsche’s reply. I reinstall Windows fairly regularly (it’s just good to do), and recently upgraded computers. During the upgrade process, both computers were running. After my new computer had been activated, my old computer started saying that it wasn’t activated. So you can reinstall as many times as you want with no problems. The copy protection exists solely to make sure that you aren’t running the same operating system concurrently on multiple computers. ---
**Author:** ![drachillix](https://avatars.discourse-cdn.com/v4/letter/d/48db29/32.png) [@drachillix](https://boards.straightdope.com/u/drachillix)\ **Post date:** [September 14, 2011, 1:29pm UTC](https://boards.straightdope.com/t/question-about-windows-licensing/596277/5 "2011-09-14T13:29:05Z")
> [@MercuryP](#): > > I can confirm lazybratsche’s reply. > > I reinstall Windows fairly regularly (it’s just good to do), and recently upgraded computers. During the upgrade process, both computers were running. After my new computer had been activated, my old computer started saying that it wasn’t activated. There is no mechanism by which MS does this. ---
**Author:** ![drachillix](https://avatars.discourse-cdn.com/v4/letter/d/48db29/32.png) [@drachillix](https://boards.straightdope.com/u/drachillix)\ **Post date:** [September 14, 2011, 1:35pm UTC](https://boards.straightdope.com/t/question-about-windows-licensing/596277/6 "2011-09-14T13:35:18Z")
> [@lazybratsche](#): > > If you’ve got a Home Premium install disk, and the laptop has a Home Premium license sticker on the bottom, you should be set. I could be wrong but I don’t think there’s a substantial difference between OEM and retail copies. Most disks floating around are OEM disks, retail copies only happen if you purchased a copy off the shelf in a nice box. The stuff you see for $99 on newegg are OEM product. They are functionally identical, the difference is licencing restrictions and support. A Retail copy can be moved as you upgrade without restriction, and comes with support provided by microsoft. An OEM copy technically is bound to one machine (yes there are ways around that) and support is provided by the manufacturer of the PC. ---
**Author:** ![drachillix](https://avatars.discourse-cdn.com/v4/letter/d/48db29/32.png) [@drachillix](https://boards.straightdope.com/u/drachillix)\ **Post date:** [September 14, 2011, 1:40pm UTC](https://boards.straightdope.com/t/question-about-windows-licensing/596277/7 "2011-09-14T13:40:49Z")
> [@Mean\_Mr.Mustard](#): > > I offered to take a look at a friend’s jacked-up laptop; as it turns out, it seems to be virus-infested. It won’t even let me download an anti-virus program. All is not lost Use another computer and download the assorted versions of rkill > **[Download RKill](https://www.bleepingcomputer.com/download/rkill/)** > > RKill is a program that was developed at BleepingComputer.com that attempts to terminate known malware processes so that your normal security software can then run and clean your computer of infections. When RKill runs it will kill malware processes... One of them should run and will shut down most active virus processes. This does not remove them from the hard drive, just shuts them off till next reboot. That way you can instal an AV app or use another more decisise remover like combofix. > **[Download ComboFix](https://www.bleepingcomputer.com/download/combofix/)** > > ComboFix is a program, created by sUBs, that scans your computer for known malware, and when found, attempts to clean these infections automatically. In addition to being able to remove a large amount of the most common and current malware, ComboFix... ---
**Author:** ![Mean\_Mr.Mustard](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mean_mr.mustard/32/3865_2.png) [@Mean\_Mr.Mustard](https://boards.straightdope.com/u/Mean_Mr.Mustard)\ **Post date:** [September 14, 2011, 2:15pm UTC](https://boards.straightdope.com/t/question-about-windows-licensing/596277/8 "2011-09-14T14:15:22Z")
Thanks for the replies. I didn’t mention this in the OP because I didn’t think it would make a difference, but now I see that it might: the infected PC is running Vista; my full install disc is Windows 7. I presume it is frowned upon - if not illegal - to share 7 with her. mmm ---
**Author:** ![MercuryP](https://avatars.discourse-cdn.com/v4/letter/m/96bed5/32.png) [@MercuryP](https://boards.straightdope.com/u/MercuryP)\ **Post date:** [September 14, 2011, 2:22pm UTC](https://boards.straightdope.com/t/question-about-windows-licensing/596277/9 "2011-09-14T14:22:16Z")
[http://answers.microsoft.com/en-us/windows/forum/windows\_7-windows\_install/is-there-a-limit-to-windows-7-activation/68a4b9c2-cdf1-4cb8-8840-fc7979d5340e](http://answers.microsoft.com/en-us/windows/forum/windows_7-windows_install/is-there-a-limit-to-windows-7-activation/68a4b9c2-cdf1-4cb8-8840-fc7979d5340e) Retail versions : 5 web activations and then phone activations for the “life” of Windows 7. OEM version : 1 activation and then phone activations when using the same motherboard used on first activation. At any rate, to answer the original question, even retail versions of Windows are bound to one machine at a time, and I’m fairly certain that it’s enforced through the online activation/Genuine Advantage process. As lazybratsche stated, everything is by key, so feel free to use whatever disk you want, but if you don’t have another key, then you’re out of luck with the laptop. If the laptop were running Windows 7, you could actually look at your license key before you wipe the hard drive and then use that again, which would be perfectly legal, though you’d probably need to do phone activation. ---
**Author:** ![Keeve](https://avatars.discourse-cdn.com/v4/letter/k/f07891/32.png) [@Keeve](https://boards.straightdope.com/u/Keeve)\ **Post date:** [September 14, 2011, 3:06pm UTC](https://boards.straightdope.com/t/question-about-windows-licensing/596277/10 "2011-09-14T15:06:18Z")
> [@Mean\_Mr.Mustard](#): > > I didn’t mention this in the OP because I didn’t think it would make a difference, but now I see that it might: the infected PC is running Vista; my full install disc is Windows 7. > > I presume it is frowned upon - if not illegal - to share 7 with her. Bingo. She’s toast, unless you can find a Vista disc. The product key on the Vista machine will not work if Win 7 is installed. The operating system that you install has to match the one on the Product Key sticker: Vista or Win7, Home or Pro, OEM or Retail, etc. ---
**Author:** ![Mean\_Mr.Mustard](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mean_mr.mustard/32/3865_2.png) [@Mean\_Mr.Mustard](https://boards.straightdope.com/u/Mean_Mr.Mustard)\ **Post date:** [September 14, 2011, 3:51pm UTC](https://boards.straightdope.com/t/question-about-windows-licensing/596277/11 "2011-09-14T15:51:52Z")
> [@Keeve](#): > > Bingo. She’s toast, unless you can find a Vista disc. The product key on the Vista machine will not work if Win 7 is installed. > > The operating system that you install has to match the one on the Product Key sticker: Vista or Win7, Home or Pro, OEM or Retail, etc. Yeah, I thought as much. I’ll leave it to her if she wants to obtain a Vista install disc. If so, I’ll help her. If not, aforementioned toast. mmm ---
**Author:** ![drachillix](https://avatars.discourse-cdn.com/v4/letter/d/48db29/32.png) [@drachillix](https://boards.straightdope.com/u/drachillix)\ **Post date:** [September 14, 2011, 7:34pm UTC](https://boards.straightdope.com/t/question-about-windows-licensing/596277/12 "2011-09-14T19:34:57Z")
> [@Mean\_Mr.Mustard](#): > > If not, aforementioned toast. > mmm Did you try my suggestion of rkill, we use that to crack EXACTLY that type of virus problem every day in my shop. ---
**Author:** ![Blakeyrat](https://avatars.discourse-cdn.com/v4/letter/b/ecd19e/32.png) [@Blakeyrat](https://boards.straightdope.com/u/Blakeyrat)\ **Post date:** [September 14, 2011, 7:42pm UTC](https://boards.straightdope.com/t/question-about-windows-licensing/596277/13 "2011-09-14T19:42:36Z")
In general, when you buy a copy of Windows, what you’re really buying is the little foil sticker. The disks are all interchangeable. ---
**Author:** ![Mean\_Mr.Mustard](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mean_mr.mustard/32/3865_2.png) [@Mean\_Mr.Mustard](https://boards.straightdope.com/u/Mean_Mr.Mustard)\ **Post date:** [September 14, 2011, 7:45pm UTC](https://boards.straightdope.com/t/question-about-windows-licensing/596277/14 "2011-09-14T19:45:22Z")
> [@drachillix](#): > > Did you try my suggestion of rkill, we use that to crack EXACTLY that type of virus problem every day in my shop. I did not, drachillix, but I will. I appreciate the advice. mmm ---
**Author:** ![Mean\_Mr.Mustard](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mean_mr.mustard/32/3865_2.png) [@Mean\_Mr.Mustard](https://boards.straightdope.com/u/Mean_Mr.Mustard)\ **Post date:** [September 14, 2011, 10:33pm UTC](https://boards.straightdope.com/t/question-about-windows-licensing/596277/15 "2011-09-14T22:33:09Z")
> [@drachillix](#): > > Did you try my suggestion of rkill, we use that to crack EXACTLY that type of virus problem every day in my shop. drachillix - So, I download rkill onto my own computer, then what…copy it to disk, then run it from the infected machine’s disc drive? At the rate the malware windows repeatedly keep opening, I’m not sure it will let me run anything. mmm