Like the queen, Windows Vista gets to celebrate two birthdays in close succession. November 30 marks the first, with the "business" launch a year ago at venues across the planet. Next January will mark the second birthday date.
While the past 12 months have been dominated by headlines over sales and uptake - or lack thereof - the operating system's first year will also be remembered for a lack of buy-in from software developers and hardware partners.
It's been a long, slow road for Windows partners. Having changed the Windows architecture with UAC, setting user defaults instead of administrator privileges, removing the graphics sub system from the kernel, and closing the kernel off to third parties, Microsoft set the barrier to certification pretty high.
And as if that wasn't tough enough, the addressable market Microsoft promised partners simply didn't materialize. Pre-launch, Microsoft claimed Windows Vista would out sell Windows XP, and be running on 400 million PCs 24 months after launch, compared to three years before Windows XP hit even half of that on 210 million.
According to latest data from NPD, Microsoft is shipping fewer boxed copies of Windows Vista than it did Windows XP at the same point in the operating systems' lifecycles.
Gartner, meanwhile, has said businesses are actually postponing their move to Windows Vista from the anticipated late 2007 and 2008 dates, to late 2008 going on 2009. One reason will be the absence of the first Service Pack - traditionally, the first Windows service pack is regarded as a first step by those in business IT to installing the latest version of Windows.
That hasn't stopped Microsoft trying to fit the facts to reality. Following the January "mass" launch Microsoft claimed to have sold 20 million Windows Vista licenses in one month. That compared to Windows XP that shipped 17 million copies in two and a half months after its 2001 launch. Licenses, though, did not translate to PCs in the hands of end users hands. Twenty million PCs were simply not sold in just one month, meaning licenses were pumped out to partners and were sitting in the channel or at OEMs, going nowhere. Proving the point, OEMs like Dell began re-stocking Windows XP.
Those nagging technical difficulties presented another problem. Users - even Microsoft's own executives - complained Windows Vista was unable to work with their systems or crashed. The issue became hard to ignore, as Acer's chief executive slammed Windows Vista for being a huge disappointment to the whole industry, picking on stability and lack of sales as problems.
Having first talked of "rumors" of problems, Microsoft 'fessed up by the summer: 4,000 drivers were causing "most" problems.
At launch, one year ago, Microsoft claimed to have "more than" 250 hardware and software products certified for Windows Vista. In the 90 days between the "business" launch and January 2007 "mass" launch, Microsoft pressed hard to get more.
This was not the ideal position for a new version of Windows to be in.