Microsoft Windows comes with a ‘key’ called the product key, a unique combination of keys and numbers that is used to validate and unlock the installed operating system. If your computer came pre-installed with Windows, then you should be able to find it on a small Yellowish sticker.
For example, in my case, it is a notebook computer, and it is located on the bottom panel. If you purchased Windows directly from Microsoft, then this sticker should be given to you with the CD/DVD.
Anyway, let’s say that you wanted to reinstall the OS but have lost the sticker that came with the Windows disc or the one on your computer is damaged, then you will run into some troubles.
For retrieving this genuine key, Microsoft advices that you contact the manufacture or Microsoft (if you purchased it from them). However, if your operating system is still functional, then you do not have to go through all that hassle as there are software tools that have the ability to retrieve this product key from the existing Windows OS on your computer.
If you are looking for a free and open-source one then you can try ‘WindowsInfo’. It shows you the current Windows version (worked flawlessly in my Windows 7 Professional 64-bit edition), product key, installer’s source (in my case it says ‘Installed from OEM Media’), current up-time and the registered user’s name. You can also export all these details into a text file as well.
WindowsInfo’s compressed downloadable file is about 8.26MB in size, which when comparing with its functions is a bit big. But I guess that is because it uses ‘wxWidgets’ for the GUI and most of its size is consumed by ‘wxWidget’ files. Nevertheless, it gets the job done :).
It supports both 32 bit and 64 bit versions. If interested, then please get it from this page.
How to run it?
As mentioned above, it comes with a compressed file, so once the download completes, extract its content to somewhere. Then look for a file called ‘WindowsInfo’ and double click on it (as shown below).