When Microsoft revved Internet Explorer to version 5.01 for Windows 2000, the company embarked on what was to become the first of many IE 5.x updates. I'm sure they didn't mean it to happen this way, but each version of IE has been considerably buggier, as well as more powerful, then the version it replaced. With Windows 2000 complete, the company embarked on what was to become two separate product updates, IE 5.01 Service Pack 1 (SP1), a collection of bug fixes for IE 5.01; and IE 5.5, a semi-major update that would add a slew of new developer features designed at making it even easier to integrate the Web into Windows. Strategically, Microsoft would make IE 5.5 part of Windows Millennium Edition (Windows Me), the last revision of Windows 98, but the product is really designed as a stepping-stone between the Win32 past and the .NET, Web-enabled future. For consumers, however, IE 5.5 is rather confusing, as it offers only a single new end-user feature (Print Preview). And for Windows 2000 users, IE 5.5 is particularly confusing, because of an odd limitation that prevents it from updating certain components on such systems.

And that's where this install guide comes in. For Windows 9x and NT 4.0 users, upgrading IE is straightforward: Simply grab the latest version off the Web and install. At the time of this writing, that's IE 5.5. But Microsoft has made things decidedly more complicated than that for Windows 2000 users, as there have been three major updates released since Windows 2000 that can update IE components. And if you don't install them in the right order, you might not be able to upgrade all of your IE-related functionality until IE 6.0.

Well, we wouldn't want that to happen, now would we? In the interests of saving you a lot of grief, let's take a look at the order in which you should install IE updates on Windows 2000.

1. Security fixes and compatibility updates
Before doing anything else, head over to Windows Update and basically install everything besides Internet Explorer 5.01 Service Pack 1 and Tools and Internet Explorer 5.5 and Toolls. This will require several reboots and some items will need to be installed independently. When Windows 2000 was first made available, there weren't many updates on Windows Update, but the site is finally starting to fill up. Make sure your system is up-to-date before you do anything else.

2. Internet Explorer 5.01 SP1 and Tools
Currently, this is the only update to Windows 2000 that lets you choose components during install, so if you've ever run an IE 4.x or 5.x setup program before, the options should be familiar. More importantly, this is the only way to update your Outlook Express and other non-browser IE components to version 5.5 (don't ask), so it's important to run this installation before IE 5.5, especially if you use programs such as Outlook Express.

3. Internet Explorer 5.5 and Tools
When you install IE 5.5 on Windows 2000, the setup program locks out the custom installation capability and instead provides you with updates to the Web browser and scripting components only. Microsoft says that this is because of the Windows File Protection (WFP) feature in Windows, which is baloney, because both IE 5.01 SP1 and Windows 2000 Service Pack 1 are able to perform this seemingly insurmountable task. But IE 5.5 is shackled on Windows 2000 nonetheless, giving you only one option: A 6 MB Windows 2000-specific download

4. Windows 2000 Service Pack 1
As mentioned previously, Windows 2000 Service Pack 1 (SP1) will update a number of IE components to the latest versions, as of August 2000. However, this update should be run last, since it's currently unclear which components it updates and whether there is any difference between it and IE 5.01 SP1. Windows 2000 SP1 can be had a number of ways--Windows Update offers a link--but you will get different installation options depending on how you choose to download the program. If you do get this option, make sure that you backup your existing files to enable a restore feature: Several SP1 incompatibilities have already come to light and you don't want to get stuck with an orphaned product if a new version of SP1 is ever released. If you don't see this option during install, don't worry: It will enable it automatically. Unlike many of Microsoft's decisions of late, this one actually makes sense. For more information about SP1, please see my review of Windows 2000 Service Pack 1.

Version numbers
Depending on which of these updates you install--I recommend all of them, in the order shown--your IE and Windows system components will be updated accordingly. The following table explains which version numbers you should see after install the components described above:

Update Win2K version IE version OE version
IE 5.01 SP1 5.00.2195 5.00.3103.1000 5.00.2919.6700
IE 5.5 5.00.2195 5.50.4134.0600 5.50.4133.2400
Win2K SP1 5.00.2195 Service Pack 1 5.00.3103.1000 5.50.4133.2400

Conclusion
Microsoft has made it too difficult for end-users to upgrade Windows 2000 and I hope that this situation changes in the future, especially given the fact that consumers will be moving to this platform in large numbers with the next release. But understanding the issues involved and installing the existing updates in the correct order will at least give Windows 2000 users the ability to run the latest system components.