Windows 7 Starter edition explained

Windows 7's 'netbook edition' -- Windows 7 Starter -- will only let you run three applications at once, Microsoft has revealed. There has been some confusion over what this means, and how it's handled if you try and open a fourth. We sat down with Microsoft to sort it out once and for all.

Firstly, a quick note about what Windows 7 Starter is. Windows 7 Starter is the entry-level version of the new OS, geared almost exclusively at the bottom end of the netbook world, in terms of performance. It doesn't include features such as Windows Media Center or Aero Glass, and Microsoft itself "recommends Windows 7 Home Premium and Windows 7 Professional for netbooks that have sufficient hardware".

The three-app limit for Starter applies only to executables, and so doesn't include system processes such as anti-virus software running in the OS's background. If you use several Web-based apps, you're also in luck, because your browser only counts as one. While, say, Internet Explorer would count as one of your three applications, opening five instances of IE wouldn't count towards your limit.

Should you attempt to open a fourth application (in addition to, say, iTunes, Firefox and Microsoft Word) Microsoft says you will be notified on-screen. And by 'notified', you can safely assume that means 'prompted to upgrade'.

This is where it gets interesting. Every single Windows 7 netbook (and indeed all laptops and desktops, too) will have Windows 7 Ultimate's components installed, but if you only paid for Starter, all you get is Starter. If you then hop on to Microsoft's Web site and pay to upgrade to Home Premium, for example, you'll get a code that unlocks Home Premium's features. Microsoft told us this will take about five minutes.

User beware: you will not be able to downgrade in the same way -- you can only go up. If you find your little machine can't handle Ultimate, it's tough cookies. Though your computer's manufacturer may provide a software restoration CD that rolls back your system to the factory defaults -- including the OS -- you'll probably lose your data in the process, so be warned.

Windows 7 is expected to be on store shelves by January 2010. You can check out all our previous coverage here to get up to speed with what's new, and keep your eyes peeled for our hands-on reports on the Windows 7 release candidate, released earlier today.

Update: CNET UK sister site ZDNet UK just received an accidental tip-off from Acer's European vice-president, Massimo D'Angelo, that Windows 7 will launch on 23 October. ZDNet UK editor Rupert Goodwins says, "it is our firm impression from the circumstances of the blooper that it's accurate."