No COA (Certificate of Authenticity) means it is counterfeit , or otherwise illegal. The COA is probably the most difficult part of the distribution to counterfeit (and have it look original) so if it doesn't have the COA, it is probably counterfeit. Another possibility is that the reseller sells each copy of Windows twice, by giving the COA (but not the CD) to customers buying a new system, and selling to others the CD (sans COA). This is illegal and unethical, but doesn't necessarily mean it is counterfeit. From Microsoft's web site:
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Consumers and resellers are encouraged to become familiar with the warning signs that can help them identify counterfeit or illegal software:
- Prices that are "too good to be true"
- Back-up disks or CD-ROMs with handwritten labels or components that appear to be of inferior quality
- Manuals that appear to be photocopied or are of inferior quality
- Software marked with a phrase, such as "For distribution with a new PC only," "Special CD for licensed customers only," "Not for retail or OEM distribution" or "Academic price - not for use in a commercial environment," that does not describe the transaction
- Microsoft OEM Windows 98 or OEM Office 2000 that is not accompanied by a user manual that incorporates a Certificate of Authenticity as the cover, as well as back-up media and an end-user license agreement that is visible on-screen when the programs are first run
Customers or resellers with questions about the legitimacy of Microsoft software should contact the Microsoft anti-piracy hot line, toll free, at (800) RU-LEGIT (785-3448) or send e-mail to piracy@microsoft.com. In addition, a list of authorized distributors and details regarding the OEM System Builder program are available at http://www.microsoft.com/oem/. >>
Now, note that there's a difference between "counterfeit" and "otherwise illegal." Counterfeit is definately illegal, just like making a burned copy. Otherwise illegal means Microsoft doesn't like it, but they may have still been paid a license for it. To be "legal" (besides not being counterfeit) according to Microsoft, you have to get it one of these ways:
a) Buy the product in a box
b) Buy the product as part of a pre-built system from larger OEMs (IBM, Compaq, etc.)
c) Buy the product as part of a pre-built or custom-built system from smaller OEMs (your local mom&pop shop)
a) will cost the most, and you'll get the product CD, install key, COA (sometimes a sticker on the box), the box itself and very limited tech support from Microsoft.
b) will cost the cheapest. Large OEMs pay around $40-50 or so to Microsoft for a license of "consumer" Windows (9x, Me). They get to distribute one copy per machine. This was part of one of the lawsuits against Microsoft. Microsoft was making OEMs pay for one OS (operating system) per system sold, even if the customer buying the system wanted an alternate OS installed. In any case, OEMs are allowed to have the OS pre-installed, plus have the CD or a "restore" CD packaged with the system. Important to note is that only one SETUP.EXE can be packaged with the system.
c) will sometimes be cheap, sometimes expensive. Why? Most of what you see on the market is either counterfeit or grey market (what Microsoft likes to call illegal, but has been paid for). The TRUE legal version is called DSP, and (for Win9X, Me) is available only as 5-packs from larger distributors. The DSP copy is the typical booklet with attached COA, shrinkwrapped to the CD. I recall the booklets saying DSP on them. The cost on these DSP copies are rediculous - about $100 a copy. It seems that Microsoft is intentionally making it difficult for small shops to compete. Most of the time it ends up cheaper. How? Well, either from counterfeit copies or grey market copies. Counterfeit ones are just plain copies, and Microsoft has not been paid for them. Grey market means that some company somewhere has indeed paid Microsoft for these products, but they are being distributed contrary to Microsoft guidelines. For instance, if a larger OEM has too many copies of a particular OS, they'll dump it on the grey market to recoup costs. But Microsoft doesn't want their software distributed this way, so they call it "illegal."