Microsoft's Nick White let us all know today that Vista SP 1 is now available for download via Windows Update. Nick has some good info on how you get begin the download process now, rather than wait until mid-April for it to automatically download.

If in running Windows Update you do not see Windows Vista SP1 listed, there are a number of good reasons for this (Eight in fact, see the whole list). Below are a few of the most common reasons why you might not see SP1 on Windows Update:

   * You have not yet installed all the prerequisite packages you need for Windows Vista SP1. To install them, visit the Windows Update control panel and click on "check for updates."

    * You have a pre-release version of SP1 and need to uninstall it before installing SP1
    * You already have it. To determine if you already have SP1 installed, Open the Start Menu, right click on Computer and left click on Properties.
    * We released SP1 in these 5 languages: English, French, Spanish, German, and Japanese. If you have any other language installed, SP1 will not yet be offered to you. (You might not even know if you have an additional language installed! Check the Language control panel to see what languages you have installed)
    * Back in February we announced that we'd be using Windows Update to help make the update as seamless as possible for our users. Windows Update will detect drivers that we know may be problematic when updating to SP1 and will not offer the service pack until an update has been installed.