Understanding Microsoft's Product Distribution.
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Microsoft Product Type Descriptions;
CD & Key
CD & Key software includes only the installation disc(s) and a single product key for activation of the product (if necessary). It is similar to OEM packaging, but does not include a Certificate of Authenticity (COA). Everything you need for installation is provided with the package. CD & Key software is only available in “full version” editions. This type of product is not eligible for support from the manufacturer, and cannot be transferred, even if the original computer breaks. The discs and/or packaging may include “promotional stamping,” but under USA copyright law, any such stamping becomes irrelevant verbiage once it reaches our wholesale market.
Retail Box software comes packaged in a cardboard or plastic box, or a DVD case. Installation disc(s) are included. It is typically eligible for free tech support from the manufacturer, and often (but not always) includes printed manuals. It is functionally identical to the software you would buy in a major electronics store.
OEM software is a full version of the software which will include the installation disc(s), Certificate of Authenticity, and product keycode/serial number (if necessary). OEM software does not come in a retail box, doesn’t include printed manuals, cannot be transferred (even if the original computer breaks), and is not eligible for free technical support from the manufacturer. Help files are normally included on the disc. OEM software is only available in “full version” editions, meaning there are no OEM upgrade products. OEM software can, however, be upgraded to future versions of the software.
Upgrade software comes in a retail box or DVD case, and includes everything a retail box product would normally include. To use upgrade software, you must be running an eligible previous version of the software on your system. The list of software you can upgrade from is included in the product description. Once the software examines your computer and finds an eligible previous version, it will install the complete version of the software.
Product Only packaging includes only the product itself (such as a cable or surge suppressor), and is not packaged in a retail box. Warranty cards and instructions are not included, and any guarantees offered by the manufacturer do not apply.
Open License software is an electronic-only version of the software. When you order Open License software, the software manufacturer issues electronic licenses directly to your organization and emails them to you. This type of software usually has a minimum license requirement, which will be noted in the description of the product. In order to process Open License software, we are required to collect end-user information to properly have the licenses registered. We will email you requesting the necessary information after you place your order.
Retail License Pack
Retail License Packs do not include any installation discs. They are only designed for adding additional users/devices to an existing setup, or for use if you already have installation discs. They are commonly used in server environments to add additional users. Certain types of license packs do not include product keycodes, as they are designed to be used on the “honor system,” granting you a license to add additional users/devices to your system.
License Only/OEM License Only
License Only software does not include any installation discs. They can only be used in conjunction with a Media Kit/OEM Media Only package. If you already own the relevant installation discs, you can purchase these additional licenses to add existing users or install on separate computers.
Media Kit/OEM Media Only
Media Kits are for installing software only. They do not include any type of licenses for actually using the software. Licenses for use must be purchased separately
Found at support,microsoft.com 4-2008 Changes can be made at their whim, so always check with them for the latest information.