Retrieve a lost CD-Key from the registry

The CD-key entered during installation is stored in the registry (and cannot be found on the install CD). One can extract the CD-key of an existing installation, though in the later versions of Windows the CD key has become encrypted. But KeyFinder can decrypt it and recover it no matter what.

In WinNT4 one can find it as pure text:

[HKEY_LOCAL_MACHINE\ Software\ Microsoft\ Windows NT \CurrentVersion]
ProductID=

Note if the ProductId has the format “12345-nnn-nnnnnnn-12345” then “nnn-nnnnnnn” is the CD-Key.

In Win2k/WinXP the key is located here but is encrypted:

[HKEY_LOCAL_MACHINE \SOFTWARE \Microsoft \Windows NT \CurrentVersion]
DigitalProductId=

If the Win2k/WinXP was installed unattended then the cd-key might be found here:

%SystemRoot%\System32\$WINNT$.INF

Related Change WinXP CD Key using WPA