>>A friend of mine found this in his inventory (unopen).
>>
>>To those interested you can send your email address or if you prefer send me a private message with youe email address.
>>
>>I'll forward these emails to my friend.
>
>If this was used to upgrade to a version after 2.6, he can't sell it. The license agreement prohibits this.

If it was found unopen(ed), it's highly unlikely it was upgraded.