Windows 7 Professional has been cracked, and can be permanently activated with OEM style instant offline activation which will pass Windows Genuine Advantage (WGA) validation, before even any Windows 7 is officially released according to Windows 7 release schedule.

All hell breaks loose when a Windows 7 Ultimate OEM DVD ISO from Lenovo been leaked and posted on Chinese forum. The ISO was quickly grabbed to retrieve boot.wim, which was then used to retrieve the OEM-SLP product key and OEM certificate for Windows 7 Ultimate.
Microsoft has updated the the SLP (System-Locked Preinstallation), a procedure that used to preactivate Windows operating system for mass distribution by major OEM (original equipment manufacturers), to version 2.1 to support Windows 7 and Windows Server 2008 R2 while provided backward-compatibility for Windows Vista and Windows Server 2008 activation. Windows Vista and Windows Server 2008 OEM activation is provided by SLP 2.0. SLP 2.1 requires SLIC imprinted in BIOS to be updated to SLIC version 2.1 too, which contains new Windows Marker.

After extracting the OEM certificate and OEM product key, it’s confirmed that Windows 7 uses the same digitally signed OEM certificate (in .xrm-ms extension) that is been used in Windows Vista. Windows Vista OEM cert can be used in Windows 7 has been explained in Windows 7 forum. As OEM certificate is digitally signed by Microsoft with its own Private Key with OEM Public Key and OEMID (part of SLIC table in BIOS). The combination of correct Private Key, Public Key with OEMID will pass SLP validation as valid Microsoft license. Meanwhile, Windows Marker is signed by OEM itself based on OEMID and OEMTableID (both belongs to SLIC) using the private key that matches the public key. Thus, the same OEM cert can be used for many different SLICs, as long as OEMID remains the same, as in the case of SLP 2.0 and SLP 2.1, although Windows Marker has changed due to different OEMTableID.

The trick is to have BIOS modded to include the SLIC 2.1. The SLIC 2.1 can be modded into BIOS physically (hardmod or biosmod) or been emulated or simulated during Windows boots up (softmod). Various SLIC 2.1 BIN has been retrieved from various notebook computer that shipped with new SLIC 2.1 in BIOS to support the free Windows 7 Upgrade Option from Windows Vista. If you just bought a new PC, it’s possible to check if SLIC 2.1 exists in BIOS. The information can be used to mod the BIOS. If you’re not technically know-how, it’s possible to request for BIOS mod assistant, or wait for Windows 7 Loader or WoW7.

Last but not least (which makes no activation cr***k works properly so far) is OEM-SLP product key for Windows 7. So far no OEM-SLP product key required to activate Windows 7 as OEM offline instant activation been leaked yet as no machine has been officially ship in Windows 7 by OEM, until now.

The extracted Windows 7 Ultimate OEM-SLP product key, 22TKD-F8XX6-YG69F-9M66D-PMJBM, can be used to activate installed Windows 7 Ultimate system, which BIOS has a valid OEM SLIC 2.1, and corresponding OEM cert, even if it’s OEM cert meant for Windows Vista. Best news is that, the product key appears to be a master OEM-SLP product key for Windows 7 Ultimate, which able to activate many OEM brands, such as HP, Dell, MSI and Lenovo. Checkout the discussion at Windows 7 forums.
Tip: It doesn’t matter if you have download and install Windows 7 RTM retail version ISO or Windows 7 RTM OEM version ISO. Just use the following commands to convert to OEM version:

slmgr.vbs -ilc OEM.XRM-MS (where OEM.XRM-MS is a valid OEM cert matching with SLIC 2.1 in BIOS)
slmgr -ipk 22TKD-F8XX6-YG69F-9M66D-PMJBM

Both 32-bit and 64-bit (x86 and x64) Windows 7 Ultimate system should and can be activated immediately. For Windows 7 Professional, Windows 7 Home Premium, Windows 7 Home Basic, and Windows 7 Starter, the OEM-SLP keys haven’t been leaked, thus can’t be OEM-activated yet. It’s expected that various Windows 7 activators, Windows 7 activation toolkits, Windows 7 Loaders and etc are expected to be released by various hackers soon. However, Microsoft may decide to block and blacklist this leaked master OEM-SLP product key. If true, other OEM-SLP keys from actual machine shipped from OEM has to be retrieved.