There is a way, you can generally buy direct from Microsoft.com (change .com to your region), I think this takes you direct to Digital River.

However you will need to compare the prices with the bought versions in the stores or to the likes of amazon.com. For instance in the US I can find A Windows 7 Home Premium Upgrade to be priced $119.99 and priced $109.99 with free shipping in amazon.com. I am not from the U.S. however and I have never bought from the Microsoft store however I think when you do buy from the Microsoft store it then takes you to Digital River.

I am a student and there are a lot of nice deals in software available for students. If you are a student, you can generally find special deals for students.

Note the store bought Windows 7 full version or upgrade discs and Student bought software product keys will all work with these .isos providing you download the correct version of Windows 7, Home, Home Premium, Professional or Ultimate.

natakuc4 , So it's better that i directly buy from microsoft store.

Any other help??

Can i buy product key after installing Windows? Is it possible?

It's not necessarily better, but it definitely is easy:

www.microsoftstore.com/.../list.true

You can buy it and activate Windows at any time AFTER installing the OS, up to 30 days before you have to activate Windows or it will stop working.

theflash1932, those in MS store are not OEMs!???

No, they aren't, but the ISO's listed in nat's wiki aren't OEM either.  You cannot download an [legal] Dell OEM DVD ISO anywhere, and you cannot buy a branded OEM key anywhere, except from that OEM with a purchased computer.

If you download the ISO's from Digital River (in nat's wiki), you are actually downloading Retail media.  If you buy from the link I provided in the MS store, they are Retail ISO's too (according to nat, it directs to Digital River).  You can install using Retail media and activate using an OEM key.  Since you asked about buying a key to use with the ISO's, I would assume you don't have a valid OEM key to use, meaning that any legit place you buy a key from will be a Retail key.

Okay I should clarify a few important points. Microsoft have 3 main licenses (each further split into the different versions, Home, Home Premium, Professional and Ultimate):

• If you are buying Windows 7 without a computer for a computer without any version of Windows (for example a home build PC or a Mac) you will typically need to buy a full retail version.

• If you are buying Windows 7 for a computer with an earlier version of Windows or a lesser version of Windows 7 you will typically purchase an upgrade version which are cheaper.

• If you are buying a computer from a manufacturer such as Dell you get an OEM license, which is much cheaper. With an OEM license, Microsoft doesn't pay full attention to supporting it of course you still get the same updates and everything however you cannot call/contact Microsoft if you have problems. Although I think they do support you for installation of Service Packs. This leaves support options to the OEM such as Dell. Another consideration with an OEM license is that they are non-transferable, a retail license is but may only be used on one computer per time. OEM licenses can be obtained without a machine, there's a kind of grey area here but it is designed for system builders such as technology enthusiasts who build and sell PCs. Of course if they are completely changing the hardware in particular the motherboard, a retail license is needed.

These .isos are retail, they will work with an Upgrade Product Key and a Retail Product Key. You will be able to activate either via Internet or by phone. These .iso files will accept an OEM product key but you must activate by the automated phone system. Thus the .isos will cover pretty much all Windows 7/Windows Vista licenses.

So what license you are purchasing depends on your system. You are on the Dell forum so the assumption is that you have a Dell with Windows 7 or alternatively you have a Dell with an earlier version of Windows and want to upgrade. For this reason Dell sell Windows 7 Upgrade versions primarily (although you can purchase from them the full version if you wish). See here Dell.co.uk for example. This may or may not be true. I would say get the license from the cheapest place you can find it and be aware of the restrictions of each. There is also one other obvious advantage of these .isos in the fact that they include Service Pack 1, store bought discs may not include Service Pack 1 but of course you can use the key from the store bought DVD with the .iso.

Providing that you then buy the same variant, Home Basic, Home Premium, Professional or Ultimate. The key you buy from Microsoft, software4students, Amazon, PC World, Dell will work with these .isos. The cost should be the main factor, if buying a physical version from an online store remember to consider shipping costs and the time it takes to post to you. Whether you trust the site/vendor should be a second important factor as software can be pirated or counterfeit thus I would be more inclined to trust Dell/Microsoft more than the likes of eBay/Amazon but it may be a bit more expensive.

Now if you want to try Windows Vista/7, do a clean install as my other wiki using one of the retail .iso files. Install the version you desire to use and skip entering a product key. The Windows Vista one lets you use it for 30 days without input of a product key, I think the Windows 7 one is more aggressive at 3 days. There will be the occasional reminder about activation. Updates should work also.

For example when updating my wiki, splitting it into Vista and 7 separately. I installed Vista 32 bit on VirtualBox, 22 days ago and thus have 8 days left. I just installed Windows 7 32 bit on VirtualBox 2 minutes ago and I have 3 days left. (Host PC is Windows 7 64 bit also).
Note the Dell SLP is input with Windows Vista, this key will not activate, if using your OEM license it is critical you use the key on the COA. I input this key only for demonstration purposes to prove that it doesn't work and to get the screenshots. Programs such as Belarc Advisor will give the OEM SLP key and not your COA key for factory preinstalled settings. The Dell System Locked Preinstallation Key is a generic Key for all Dell systems running that variant of Windows. Dell Reinstallation Media will detect a Dell BIOs and will install this key pre-activated only and if only the system has a Dell BIOs.

Installing Windows 7 on your machine before purchasing it is recommended by me as you can assess the machines performance once you have the majority of your programs installed. 

It is a similar story for the Microsoft Office although store bought Home and Student versions are generally recommended as most Home users usually just use Word, Excel and Powerpoint and you get to install it on 3 computers opposed to 1 (as in the OEM version).

If you use Visio, Outlook, Access and Publisher like me you will need to get a Professional Plus License.

How much does it cost for a single activation key? What other software comes with it?

You will need to buy from the Microsoft Store unless you are a student, there may be a specific deal. If you buy WIndows you will get only Windows. Microsoft Office has to be purchased separately, the programs you get will depend on the version you install.

Microsoft has deals for Students but Most Schools have a VL Licence and Media that you buy from the book store at the school.

• Windows For Students | Microsoft.com

  www.microsoft.com/Student

  Check Out Student Deals, Events & Contests on Windows For Students!

• Office 2010 for Students - Buy Office Professional Academic.

  www.microsoftstore.com/Office_Academic
  

  $99.95 for College Students Only.

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