Answers to frequently asked questions about Windows product keys

Windows product key is a product that attracts a lot of questions. For those who have wondered about finding lost Windows product keys or other standard activities, these tips can be helpful.
You can not reinstall Windows without a valid, unique product key, so it's no wonder so many people are trying to find their Windows key.
This FAQ will help answer some of the more common questions about the Windows product key.
"I heard that an active Windows product key is included somewhere on the Windows DVD / CD / Image, is that right?"
No, it is not ... with a small exception.
If you have a retail copy of Windows, be it Windows 10, Windows 8, Windows 7 professional product key, etc., there will be no product keys stored anywhere on the disk or ISO image.
However, if you have a recovery disc from the mainframe manufacturer, the product key may be stored in a file on disk but it will not work when reinstalling Windows.
This product key, if it exists, is the generic product key that Microsoft allows your PC builder to use when mass-producing PCs. In other words, everyone's disk has the same product key. Your only key to use when reinstalling Windows will be the lock on the sticker on your computer.
Activation of Windows will fail if you use this product key to install Windows. If you made this error, simply change the product key to the code on your main product label and then try reactivating Windows.
"Can I use the same product key to install Windows on multiple computers?"
Yes and no.
Yes, technically, you can use the same product key to install Windows on as many computers as you want - one hundred, one thousand ... look for it.
However (and this is a big one) it's not legal and you will not be able to activate Windows on multiple computers at the same time.
After a certain period of time, Windows activation is required to continue using the operating system, especially in newer versions of Windows.
"Can I use the product key from a Windows version to install another version of Windows?"
No you can not. Windows product keys are exclusively associated with a specific Windows version.
For example, you can not install Windows 7 Home Premium with a Windows 7 Professional product key, nor can you install Windows Vista Business using the Windows 10 Home product key.
You can only use your product key for the specific Windows operating system version that is encrypted.
"Can I use someone else's Windows CD / DVD to install Windows on my computer as long as I use my original product key?"
Yes you can. Windows product keys are not tied to specific disks or images, only for specific Windows versions (see question above).
In other words, you can use a retail copy of Windows 8 from a friend to reinstall Windows on your computer as long as you use your unique Windows 8 product key.
Do you have questions about the Windows product key we have not answered above?
If your question is more about searching for a lost product key or using a lock search program, see our Key Search Key FAQ for help.
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