Microsoft makes Windows 7 available to MSDN subscribers & unveils simple Vista upgrade chart…

With the worldwide launch date of October 22 fast approaching and the final code signed off, Windows 7 is now starting to trickle through some distribution channels. Microsoft TechNet and MSDN subscribers can now download Windows 7 RTM (released to manufacturing) and while a direct upgrade from the release candidate (RC) isn't officially possible, there is a way around it .

Following the Windows 7 E edition confusion earlier in the week, Microsoft has also announced the upgrade options for the different editions — Windows 7 Home Premium, Windows 7 Professional and Windows 7 Ultimate. But if you thought upgrading to Windows 7 would simply be case of buying the version you fancy and slipping in the DVD, think again…

As the chart shows, only a few versions of Windows Vista can be upgraded to Windows 7 and most require a clean installation — as will moving up from Windows XP. In short, installing like-for-like versions (Vista Home and 7 Home, for example) won’t require wiping your hard disk and reinstalling your applications and data from scratch.

One thing to bear in mind is that installing one version of Windows over the top of another has always been a recipe for disaster, so we’d advocate a fresh install of Windows 7 whatever your upgrade position. Yes, it’s a monumental inconvenience, but it’ll ensure that your Windows 7 experience starts off on the best foot.

Finally, Microsoft has updated Windows XP Mode for Windows 7 to a new release candidate. Windows 7 can’t run all Windows XP programs, so Windows XP Mode is essentially a self-contained and pre-configured virtual PC for those old programs you can’t do without. The Windows XP Mode release candidate is available for download now — just remember that you need a PC with a processor that’s capable of hardware virtualisation, plus at least 2Gb of RAM, in order to use it.