Microsoft has pinned its hopes for getting businesses to buy into Vista on the release of Vista Service Pack 1. So the company pushed SP1 out the door before it was ready, and now early adopters are discovering that Vista, with or without SP1, still isn't business-ready.

This comes as no surprise to me. I knew that Vista SP1 was, at best, half-baked when Microsoft announced that Vista was being released to manufacturing Feb. 4 but really wasn't going to made available, even to TechNet and MSDN members, until mid-March.

Based on recent news, I'm beginning to think that saying Vista SP1 will begin arriving in customers' hands by mid-March may be optimistic.

It was bad enough that that we always knew Vista SP1 would require users to reinstall some drivers. Once a driver is in place and working, why should a patch require anyone to reinstall it? What about if the driver is for a network or graphics card? Won't reinstalling it prove more than a bit challenging?

Now, Microsoft has pulled from circulation a so-called pre-Vista SP1 patch, update KB937287, because it fouls up some Vista PCs and prevents them from starting up. As usual, Microsoft claimed it wasn't that big a deal: "We believe this problem only impacts a small number of customers."

Funny, I got the bug on one of my two Vista systems and Microsoft Watch columnist Joe Wilcox got it on one of his three systems. I don't know about Joe's PCs, but mine were run-of-the-mill Hewlett-Packard systems. Tell me again how this bug will only impact a small number of customers.

Oh, and by the way, what's this pre-Vista SP1 patch bull? If it's a needed patch to install Vista SP1, isn't it really part of Vista SP1? Isn't this proof positive that SP1 RTM was not ready to go? I certainly think so.

Microsoft is also telling us that some Vista—not XP, Vista—programs won't work with Vista SP1. For the full list, visit Microsoft and you can see the Vista application list for yourself. However, here are some samples of what you can expect to fail under the new, "improved" SP1.

A number of security programs simply won't start under Vista SP1. These include Trend Micro Internet Security 2008 and Zone Alarm Security Suite 7.1. A trio of programs is already known not to run with Vista SP1. One is a game client, Free Allegiance, for—of all things—a Microsoft game. The others are Iron Speed Designer, a Web application development program, and Xheo Licensing, a copy protection program. There are also several programs that do run, but not at all well, under SP1. These include the New York Times Reader program and Novell's ZENworks Configuration Management agent.

Then there are the Vista SP1 application problems that Microsoft knows about but doesn't tell you about in its list of problems. For example, Vista SP1 doesn't come with the GPMC (Group Policy Management Console). So, if you, like most system administrators, use a client desktop to manage your AD (Active Directory) groups, Microsoft's recommendation, hidden away in Vista's release notes, is, "If you must run the GPMC from a computer running Windows Vista, do not install this release of Windows Vista SP1."

Of course, these are only the problems Microsoft admits to knowing about. To quote Microsoft, "This article should not be considered a comprehensive list of programs that experience loss of functionality when they run on a Windows Vista SP1-based computer."

Here's the real problem. Vista SP 1 is not RTM-ready. It's not ready for use. It's almost certainly not going to be ready in mid-March. It's not ready. Period.

Even when it does get here, based on what I've seen of it, Vista SP1 isn't going to give anyone a reason to switch to Vista. Vista is still slow. User Access Control is still a pain, and software and hardware incompatibility are going to remain problems.

If you want to keep running Windows, Windows XP SP3, not Vista SP1, is what you want. I'm no fan of Windows, but I've been running Windows XP SP3 RC1 (Release Candidate 1) for several months now. It's the best Windows client operating system I've ever used. Even though it's only an RC, and not even the most recent one, XP SP3 RC2, XP SP3 RC1 has run without trouble for me both on native hardware and on a VirtualBox virtual machine.

So, as I see it, you can stick with XP, using SP3, which I think for people who are already using and happy with Windows is a fine decision. Or, if you want something better but different, you should look to desktop Linux or a Mac. But the one new operating system option that you must avoid is Vista. Even with SP1, it just isn't a good choice.