"Many (if not all) users who took advantage of Microsoft's Vista Family Discount have been issued invalid installation keys and cannot install Windows Vista Home Premium. Microsoft says, 'There is no expected time period for a fix at this time.' According to the article, the keys are valid for something, just not Windows Vista. The CSR I spoke with was unable to tell what the key was for, but it did appear to be a valid key, for something.
In the past Microsoft has just issued new keys when this happened. Perhaps it's just too simple to issue these folks new keys and send them on their way."
http://www.neowin.net/index.php?act=view&id=37734
http://it.slashdot.org/article.pl?sid=07/02/01/239242