How can I identify illegal Microsoft software?

From Microsoft Outlook 2002 Help
There are several warning signs to alert you to the fact that the software products installed on your hard disk at the time of purchase or available on the retail store shelf are illegal. For instance, Microsoft legally licenses Microsoft MS-DOS, Microsoft Windows version 3.1, Windows 95, and Windows 2000 among other products, to computer manufacturers to include with their computers for sale. However, Microsoft's agreement with computer manufacturers prohibits them from selling and/or distributing Microsoft products by themselves, without an accompanying computer.

Generally Microsoft software distributed on the retail shelf are manufactured only by Microsoft and should not bear the trade name of any other company. Microsoft software distributed on the retail shelf should never include on the front cover of the user's guide a line such as the following: "For Sale Only With A New PC," "For Distribution Only With A New PC," "For Distribution Only With A New PC," or "For distribution with new PC hardware only. Not to be sold as a stand-alone product."

Additional warning signs of illegal software products include:

No End-User License Agreement (EULA).
No Certificate of Authenticity for most products accompanying a new computer system.
No fulfillment mechanism (such as a mail-in card) for backup disks and/or manuals for software preinstalled on a new computer that does not come with packaged software inside the computer box.
No backup CD-ROMs, manuals or quick start guides, , EULA, and/or Certificate of Authenticity included as packaged product inside the computer box.
The backup disks that the computer dealer or store gives you contain handwritten labels, are not shrink-wrapped, and/or appear to be inferior in quality.
The manual(s) that the computer dealer or store gives you are photocopied, are not shrink-wrapped, and/or are poorly printed.
The person who sold you your computer offers to install software for free — or for a nominal fee — at the time you purchase your computer, without providing packages for the software.
Product upgrades available on the retail shelf do not contain the specified security features (including Certificate of Authenticity label for all retail Microsoft products).
The operating system product (including MS-DOS, Windows, Windows for Workgroups, Windows 95, Windows 2000 and Microsoft Windows NT software) that you acquired from the retail shelf without also purchasing a new computer contains on the front cover of the user's guide a line such as the following: "For Sale Only With A New PC," or "For distribution with new PC hardware. Not to be sold as a stand-alone product."