I tried to reinstall OS on my Vaio using retail 7SP1 DVD and VAIO's activation key (which I had to extract as it's not written on the system case). This didn't work. Perhaps I need to find Windows 7 (pre-SP1), or should I not even bother?
They normally do not. You need the appropriate key.Do OEM activation keys always work with retail DVDs?
The Key which you probably extracted would have been the OEM_SLP Key with which the machine shipped.
That key will NOT activate a retail/TechNet/MSDN install.
You MUST use the one from your COA sticker - which may be inside the battery compartment - for such installs.
Computers that come pre-installed with Windows from large manufacturers usually come with two Product Keys.
OEM SLP: This is the key that came in Windows (from the factory). It works by connecting to a BIOS flag (the SLIC table) found only on computers from that Manufacturer. It also checks for the existence of proper matching licenses in the OS itself. Once it sees both, it self-activates every time the machine is rebooted.
COA SLP: This is the key seen on the sticker located on the side, bottom or in the battery compartment of your machine. This key is for use if the OEM SLP self-activation stops working for whatever reason.
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