This is a legacy guide. The procedure has been made much easier to follow. Contents • • • • • • • • What is Original Equipment Manufacturer System Locked Preinstallation Activation? Examples of Microsoft’s Major Partner Original Equipment Manufacturer (OEMs) are: • Alienware/Dell • Lenovo/IBM • HP/Compaq • ASUS • Acer • Samsung • Sony • Toshiba • MSI • Fujitsu Microsoft Major Partner OEMs preinstalled Windows 7 on millions of machines. In order to save production time these Major OEM licenses utilised a BIOS based activation mechanism. The conventional way would have required the OEM to input a unique 25 digit product key and call Microsoft for every single machine This BIOS based activation mechanism is called OEM System Locked Preinstallation as an activation mechanism.

Customised Windows 7 installation media inputs a generic product key known as a System Locked Preinstallation (SLP) key which results in offline product activation if and only if the System License Internal Code (SLIC) is valid i.e. The system has an eligible system BIOS. For more details on determining the SLIC see my guide. Lets take Dell and the Edition Windows 7 Professional for example. Every single Dell PC shipped with Windows 7 Professional OEM has the same product key 32KD2-K9CTF-M3DJT-4J3WC-733WD and this will show up in system properties as Product ID: 00371– OEM- 894 (the first 5 digits differ depending on language, English is shown). A Dell Branded Windows 7 Professional Reinstallation DVD will automatically select to install Windows 7 Professional and input this product key and offline product activation if and only if the system has an eligible Dell BIOS and has been sold with Windows 10 Pro OEM (via downgrade rights), Windows 8.1 Pro OEM (via downgrade rights) or Windows 7 Professional OEM.

Lets take Dell and the Edition Windows 7 Home Premium for example. Every single Dell PC shipped with Windows 7 Home Premium OEM has the same product key 6RBBT-F8VPQ-QCPVQ-KHRB8-RMV82 and this will show up in system properties as Product ID: 00359– OEM- 895 (the first 5 digits differ depending on language, English is shown). A Dell Branded Windows 7 Professional Reinstallation DVD will automatically select to install Windows 7 Home Premium and input this product key and offline product activation if and only if the system has an eligible Dell BIOS and has been sold with Windows Home Premium Pro OEM.

Note if your OEM e.g. Dell have only certified a particular model to run Windows XP or Windows Vista, there will not be a Dell BIOS update available and hence the system will not be certified for Windows 7 OEM System Locked Preinstallation and Product Activation will fail. To identify if your system has been installed using a Microsoft’s Major Partner OEM SLP you will have a product ID of the form: • xxxxx- OEM– 899xxxx-xxxxx You may check your activation status by pressing [Windows] and [Pause Break] or by going to Start and right clicking computer and selecting properties. If there is no OEM in the Product ID you have a Retail or Volume license and these licenses are not supported with this guide Note if the product ID has the form: • xxxxx- OEM– 910xxxx-xxxxx You have Windows 7 installed via the unique 25 digit product key from the Code of Authenticity (COA) affixed to your computer.* This activation mechanism works however OEM System Locked Preinstallation is in general preferred. * It should be noted that there are two very poorly understood additional OEM licenses which may lead to confusion. These two licenses are Commerical OEM System Builder Licenses and Manufacturer Refurbisher OEM Licenses. These licenses do not have OEM System Locked Preinstallation and are hence not supported in this guide.