Selling a computer w/ Windows installed but w/o COA – legal?

[pianowizard]

Many people sell computers on eBay with Windows installed, but these computers either don’t have an COA sticker or have one for an older version of Windows. For example, the X22 that I recently purchased has a COA sticker for Win2000 but the seller sold it with WinXP installed. Is that legal? If not, how come eBay allows such sales? (BTW, I am now selling this X22 and to be perfectly legal, I downgraded the OS back to Win2000 using the product key on the COA sticker).

Suppose the answer to the above question is “It’s illegal”. What if the version that’s installed is a really old one, like Win95 or Win98? Microsoft stopped selling them so long ago, so would they still mind people installing them illegally?

[dsvochak]

If there's a COA attached, you can go back but not forward, eg. if there's a W2K COA, W2K, W98, etc would be legal but XP wouldn't be. Unless, of course, you have a legal copy of XP.

If there's no COA attached, it's not a technically a legit copy of Windows. If there's a COA attached and no OS supplied, the seller is violating the EULA (OS and machine are one).

As a practical matter, if it's a thinkpad and there's no COA attached, you could probably load the OS that came with the machine from restore disks and be legal. (OS and machine are one). And I emphasize the "probably".

I think the reasons eBay allows the sales are 1) it's hard to keep track of; 2) no one, or virtually no one complains; 3) they're more concerned with illegal/pirated copies of software.

[yossarian]

Probably not the best idea to try Win98. Microsoft are ending their windowsupdate support for it in June or July of this year.

[Aroc]

You could always put a copy of Linux on it.

[BigWarpGuy]

You could install either ReactOS http://www.reactos.org or FreeDOS http://www.freedos.org on it? Both are free.