If online activation fails, you can use the method by running slui 4 in the Run dialog (Win+R). How to get your product key for Windows 7/8/10

Be cautious of websites offering keys at "too good to be true" prices (e.g., under $20), as these are often illegitimate or temporary keys that may fail activation later. How to Find Your Existing Key

If you already own a computer that had Windows 7, you might not need to buy a new key:

Some licenses are specifically sold for refurbished PCs and may be available at lower costs, often around $50.

Finding a legitimate Windows 7 product key is difficult today because Microsoft ended mainstream support for the operating system in 2015 and extended support in 2020. As a result, Microsoft no longer sells Windows 7 licenses directly. Where to Buy a Windows 7 Product Key