Quote: Originally Posted by whs
If your product key pertains to a full retail version, you can use it. If it is an OEM, it will not work besides being illegal.
Starting with Vista all retail installers will reinstall both retail and OEM Windows of your version. If you have a Product Key it will work for the licensed version only, and may require a quick robocall to MS to sort out the key.
We cannot link to downloads as it encourages piracy, so it is best you borrow or find a retail installer (not a branded Recovery Disk). If you cannot find your version, then you can extract the ISO using ImgBurn, unlock all versions using the ei.cfg removal tool, then burn to DVD an all versions DVD to install your version with key.
The product keys are language-specific except in Ultimate which features language packs. The expert on languages here is Kari if you need to ask him directly.