Open the Start menu, type slui.exe 4 into the search bar, and press . Select your country or region from the drop-down list.

The indicates you are using an OEM (Original Equipment Manufacturer) version of Windows 7 Ultimate that was likely pre-installed on your computer . It is important to distinguish that a Product ID is not a Product Key ; the ID identifies the software version, while the Key is the 25-character code required for activation. Where to Find Your Windows 7 Ultimate Product Key

If you are trying to reinstall Windows 7 Ultimate using this ID or its corresponding master key, you are likely encountering activation errors. This happens for several technical and policy reasons:

There are several types of product keys for Windows 7 Ultimate, including: