Microsoft really doesn't want you to know this, but many of your existing applications won't work with Vista. In fact, some brand new products won't work with Vista.

At the top of that list of "It doesn't work," we find, believe it or not, Microsoft new music player, Zune. Yes, that's right; Microsoft's iPod killer doesn't work with Vista.

Not only will Zune not work with Vista, it also doesn't work with all media files that are protected with Windows Media DRM (Digital Rights Management). So much for PlaysForSure!

Microsoft promises that Zune will eventually work with Vista, but don't you find it a little scary that the boys from Redmond couldn't get their number one Christmas toy to work with their number one operating system?

Moving closer to business, let's take Microsoft's recently released scripting system, PowerShell. This scripting language, formerly known as Monad, would have made Vista management much easier ... except it doesn't work on Vista. Server 2002 and XP, yes. Vista, no.

Resource Library:

Now, Microsoft says it will be ready by January 31, 2007. Remember when Monad was going to be in Vista? I do.

Too techie for you? Then, consider if you will, Windows Live Messenger 8.0 and the beta 8.1. Both IM clients blow up after a few hours of use on Vista.

Oh, and the new IM client from AOL, AIM 6? I can now attest from personal experience that it goes "boom" too on Vista.

As someone who lives and works on IM all day every day, I'm not a happy camper. This isn't super techie stuff. They're freaking instant message clients. How hard can this be?

It's not like say the Cisco VPN client, which I also must have for work, and which doesn't work with Vista.

Vista also doesn't want to work and play well with CheckPoint VPN-1. Still, VPN's are more complicated. Of course, with business people on the road, support for VPNs, and not just Microsoft's own, is absolutely critical. Making sure the major VPNs work with Vista should have been a top priority for Microsoft.

Now, I do understand why some software will no longer run on Vista. 16-bit software, for example, including my ancient but still useful copy of Norton Commander, will no longer be supported.

That said, I do wonder a bit why many major anti-virus programs, such as AVG Free, Symantec AntiVirus Corporate Edition for Vista, and Kaspersky Anti-Virus & Kaspersky Internet Security 6.0 are all reported to crash and burn.

Microsoft releases Vista to developers. Click here to read more.

Could it be because Microsoft wants to cut the security software companies out of their business?

You should also know that some of Microsoft's own programs won't run with Vista. For example, Microsoft's own Virtual PC 2004 won't work.

Neither will Visual Studio .NET 2002, Visual Studio .NET 2003, and Microsoft SQL Server 2000. Visual Studio 2005 SP1 will work... sort of.

So, if any of you developers out there are planning on creating.NET 1.1 applications in Vista, forget about it!

As for games and media programs, good luck! Some won't work. Some will work, albeit badly, and a few will do just fine.

One thing for certain though is that if your 2005 or older game uses OpenGL for better 3-D graphics performance, it will not perform well on Vista.

Here's the bottom line. Many programs—and not just the ones I mention above—are not going to work with Vista. At least they're not going to work well with it.

For now—for the next few quarters—the wise IT manager is not going to move any production systems from XP, or earlier, to Vista. It's that simple.

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