Microsoft said:
A new Windows license is not required for a refurbished PC that has:
(1) a Certificate of Authenticity (COA) for a Windows operating system affixed to the PC, and
(2) the original recovery media or hard-disk based recovery image associated with the PC.
The COA constitutes proof that the PC is licensed for the version of Windows named on the COA and the
refurbisher can use either:
(1) the original recovery media or
(2) the original hard-disk based recovery image to re-install the operating system software named on the COA.
If the refurbisher does not have the original recovery media, they may be able to obtain the recovery media from
the original manufacturer of that PC.
A new Windows license is required for a refurbished PC if:
(1) the refurbisher cannot obtain the original recovery media or
(2) the PC does not have a hard-disk based recovery image.
Then, the refurbisher must purchase a new license in order to deliver a genuine Windows operating system
experience with the refurbished PC.
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