Original Equipment Manufacturer (OEM) versions of Microsoft software are licensed to PC manufacturers through two separate channels - large PC manufacturers and smaller System Builders. In the fall of 2001, new program-specific COA were introduced with advanced security and tracking features and the How to Tell web site address. A COA should always accompany the product with which it is associated. COAs cannot be purchased separately.

Original Equipment Manufacturer (OEM) versions of Microsoft software are licensed to computer manufacturers through two separate channels - large computer manufacturers and smaller System Builders. In the fall of 2001, new program-specific COAs were introduced with advanced security and tracking features, and the How to Tell web site address. A COA should always accompany the product that it is associated with. COAs cannot be purchased separately.

This COA has a holographic foil string on the right side.

This COA has an embedded thread woven through on the left side.

Versions of Office that are distributed with computers built by a System Builder will have the words "OEM Product" in big bold letters towards the upper left corner of the COA. Versions of Office that came from large computer manufacturers will have the name of the computer manufacturer on the COA label instead.

Prior versions of Microsoft application software will have a slightly different COA. Versions of Office that are distributed with computers built by a System Builder will have the letter D in the middle left-hand section of the COA, denoting it came through the distribution channel. Versions of Office that come from large computer manufacturers will not have the letter D in that section of the COA.