Upgrading to Windows XP from Windows 9x/Me
Windows XP Installation and
Upgrade, Part Four
The vast majority of people
who upgrade to Windows XP will take an existing Windows
98, 98 SE, or Millennium Edition (Me) installation and
upgrade it in-place. However, this upgrade isn't without
pitfalls. Windows 9x/Me and XP may look similar, but
they're built on two completely different technology
platforms, and it's actually sort of amazing that an
upgrade between them can take place at all. Windows 9x/Me is based on
DOS, a 16-bit command line OS that debuted in 1983. XP,
however, is based on the stable and reliable 32-bit NT
platform, which first debuted in 1993. It is the
technological successor to Windows 2000, not Windows
9x/Me.So why is
such an upgrade even possible? Well, Microsoft has been
working for almost a decade at melding its
consumer-oriented 9x line with NT. The first step
occurred before NT was even released, when Microsoft
decided to give NT the Windows 3.x user interface,
making it easier for users to move from one platform to
the next. However, in the early days of NT,
compatibility was a nightmare: NT could run some DOS and
Windows applications (albeit slowly), but it could work
with only a small subset of the hardware that was
available to DOS/Windows users.
In 1995, Windows 95
became the
first DOS/Windows release to feature NT technologies, in
the form of the Win32 API, which programmers use to
create 32-bit Windows programs. The version of Win32 in
Windows 95 was actually a bit different than that used
by NT, but it was a start. Future NT releases, such as
NT 4.0 and 2000, closed the gap, and 2000 added a lot of
important 9x features like Plug-and-Play support,
hardware-accelerated DirectX support, and the like. And
later 9x releases, especially Windows Me, incorporated
some reliability and stability technologies, though the
inherent instability of the underlying platform
undermined much of that work.
But over the past five
years or so, the 9x and NT lines have been converging.
In Windows 2000, Microsoft finally made it possible to
upgrade 98 machines to an NT-based product, though the
company only supported business oriented applications
and hardware. Finally, in XP, it's possible to take
Windows 98 (or newer) and upgrade it to a modern,
reliable OS, one that can stay running day after day.
And most of your applications, games, and hardware will
actually work too. It's sort of amazing.
How they did it
Upgrading
Windows 9x/Me to Windows XP is actually a bit of a
misnomer. When you upgrade such a system, Microsoft
actually examines your installation, moves your documents and
personalized settings to a backup location, and then
performs a clean install of XP. Then, it goes back
and applies those personalized settings to the new OS
and moves your documents into the correct location (My
Documents, which is located in a different place in XP
than it was in 9x/Me).
|
