When Microsoft moved mainstream versions of Windows from the DOS-based 9x code base to the NT code base with Windows XP (see my review), everything changed. Previously, consumer-oriented versions of Windows, such as Windows 98 (see my review) and Windows Me (see my review), provided superior compatibility with both software programs and hardware devices. But Microsoft's NT-based operating systems, such as Windows 2000 (see my review), offered superior reliability. For this reason, consumers generally stuck with 9x-versions of Windows, while business users, developers, and power users moved to NT-based Windows versions.

Windows XP proved to be the best of both worlds. Today, it is the dominant operating system worldwide, with an estimated 450 million desktops today running XP. With XP, Microsoft solved the age-old compatibility vs. reliability problem by making its most reliable OS more compatible. (Curiously, Microsoft tried the reverse as well, with Windows Me, by tacking reliability features on top of the creaky 16-bit DOS-based system. The results were either fantastic or utterly horrible, depending on whom you asked.)

So here we are five years later and Windows Vista has arrived. As a direct successor to Windows XP (well, Vista is technically based on Windows Server 2003, which was itself based on Windows XP), Windows Vista inherits everything that was good and bad about that system. How it improves from there is, of course, up to Microsoft. In the case of security, for example, Windows Vista is dramatically improved, as we discussed in the previous part of this review. As for reliability, Windows XP has proven quite successful for users. The system crashes far less than its predecessors, and is generally quite well-regarded from a reliability standpoint. My own experience with XP has been stellar: I haven't seen a blue screen on XP in quite some time. And while it's still early, my experience with Vista has been even better.

Reliability features

For Windows Vista, Microsoft has turned reliability up to 11. Much of the improvements come from deep, under-the-covers improvements that help prevent common causes for crashes, hangs, and other similar issues, new diagnostic and repair tools and technologies that help keep systems stay up and running even when there is a problem, and a deeper integration and reliance on Windows Update and related technologies, which constantly work to improve the reliability of Vista by providing updated drivers and other software improvements.

In this part of my increasingly out of control Windows Vista review, I'll highlight some of the reliability features you're likely to run into on a regular basis. Frankly, there's a lot more going on than the end user features I'm discussing here, but you have to draw the line somewhere. I'll try to cover Windows Vista's low-level reliability features more completely in future Feature Focus articles.

Reliability Monitor

Windows has long sported a Performance Monitor utility that allows you to monitor, at a very low level, the performance characteristics of your PC in real time using a scrolling set of counters. It's still there in Windows Vista, and it's as useful as ever. But Microsoft has also added an amazing new Reliability Monitor that is, perhaps, even better. What this utility does is monitor the reliability of your system, over time, so you can see both how the reliability is trending over time and what caused the problems you've had. It is absolutely one of my favorite new features in Windows Vista.

On the day you install Windows Vista, your system is assigned a reliability rating of 10, the highest possible score. Over time, things can only get worse: Each day there is a problem--an application that crashes, a hardware device that fails, a Windows component that gives up the ghost, or any other failure--your PC's reliability index goes down. If there are no problems at all in a given day, the reliability index will go up, but slowly. Over time, you'll see a nice graph that visually shows you how your PC has fared over time, along with little icons you can click to discover what the exact problems were. It's wonderful.

For example, I installed Windows Vista on my Lenovo ThinkPad T60 on November 8, 2006. The Reliability Monitor reports that I installed a number of applications that day as well, including Adobe Acrobat 7.0 Standard, Adobe Photoshop Elements 5.0, Apple Software Update, and so on. The majority of these installs were successful, though a few--like the Adobe Help Center--failed, bringing down my reliability index. More problematic, I had four application failures that day: Adobe Update Manager, Microsoft Outlook, and Internet Explorer (twice) all crashed. I ended the day with a reliability index of 7.66.

The score then went up and down over time like a stock ticker. It hit a low of 2.29 on November 22, when I experienced a bizarre number of recurring RunDLL32.exe failures, all of which displayed an accompanying dialog I had to deal with (the errors were related to some incompatibility with MPEG files I had downloaded and tried to play through Windows Media Player; I only got the behavior to stop when I zipped up the files and deleted the originals). Previous to that, the score was a semi-respectable 6.15, and it's been inching back towards that score ever since.

The Reliability Monitor is an incredible addition to Windows because it both provides an accurate picture of the system's reliability and shows you what, exactly, caused the problem. The only problem with this tool is that it's somewhat hidden in the Computer Management console. To get to it quickly, just open the Start Menu and type "reliability" (no quotes) then tap ENTER. You'll see Reliability Monitor in the left of the window that appears.

Backup and recovery

It's astonishing to me that Windows hasn't included better backup and recovery software. In Windows XP, Microsoft shipped a half-hearted solution at best: It included a decent backup solution, one that required a technology called Automated System Recovery (ASR) in which to function fully. The problem is that XP Home Edition doesn't include or support ASR, so Backup on that system was an optional manual install off the XP Home CD-ROM. And users who did install it could only use Backup for file backup and restore, and not for recovering the system to a previous known-good state.

In Windows Vista, the backup and restore situation is a bit more complicated. On the plus side, Microsoft has blessed Vista with a far more impressive set of backup and restore features. Sadly, however, Vista also features the weird stratification of backup and restore features that dogged Windows XP. Put more simply, you only get some backup and restore features in certain Vista versions, and those who opt for low-end versions will find themselves missing some key features.

Here's what I mean. Windows Vista supports three backup and restore and features. These include Backup and Restore Center, Windows Backup, and Windows Complete PC Backup, and I'll explain each below. (A fourth related feature, System Restore, isn't technically a backup and restore feature because it's concerned more with repairing system files, but this feature is absolutely all about reliability and carries over from its first appearances in Windows Me and XP.) Not all Vista users will gain access to all of these features, however.

If you look back at Part 2 of this review, you'll see that Windows Vista Home Basic cannot perform automated scheduled backups, as can the other editions. And neither Windows Vista Home Basic nor Home Premium support system image backup and recovery, which is a plain English way of saying that they do not include the Windows Complete PC Backup feature.

Now that we understand the limitations, let's examine what these features do, exactly.

Backup and Restore Center is a nice front-end to all of Vista's backup and restore features (it also includes a handy link to System Restore). This application includes links for backing up and restoring files and folders and, in the case of Vista Business, Enterprise, and Ultimate, a link to the Windows Complete PC Backup tool.

Windows Backup is a nicely-made wizard-based utility that can backup files and folders to a hard drive, CD, DVD, or network share. You can choose exactly what types of files to backup—pictures, music, videos, email, documents, recorded TV shows, compressed files, or any additional files of your choosing, schedule how often this backup will be scheduled (but not in Home Basic, which only supports manual backup), and restore entire backups or just the particular files and folders you need. Windows Backup is a truly useful addition to Windows Vista and much nicer than the Backup utility that shipped with Windows XP.

Windows Complete PC Backup is a unique addition to Windows Vista. There is nothing like it in previous Windows versions, but you can buy third party utilities, like Norton Ghost that are similar but more difficult to use. What Complete PC Backup does, essentially, is store a compressed version of your entire PC installation, called an image. This image is a snapshot of your PC's configuration at the moment you created the backup, so it includes all of your configured options, documents, installed applications, and everything else on the system. Microsoft uses its VHD (virtual hard disk) format, originally developed for Virtual PC, to create this image. And you can restore it later if something goes horribly wrong, bringing your PC right back to its state when the image was first created. (Note that doing this will of course wipe out the PC and anything that's been added to it since the image was created. For this reason, Complete PC Backup is a "nuke from space" solution that will typically only be used in restore mode in the event of an emergency.)

Because of what it does and the way it works, Windows Complete PC Backup cannot save the image file on the PC's main hard drive (or "system drive"). So you will need a second hard drive (formatted with the NFTS file system) or a large collection of recordable DVDs to use this utility. If you do choose to restore a Complete PC Backup, you will typically do so by booting your PC with the Windows Vista DVD and going into the product's Windows Recovery Environment.

Despite some silliness with the home-oriented versions of Windows Vista, these backup and restore utilities are all excellent and they collectively provide much more elegant backup and restore functionality than is possible in Windows XP without purchasing third party utilities.

Windows Shadow Copy (Previous Versions)

In Windows Server 2003, Microsoft added an amazing file server feature called Windows Volume Shadow Copy that helps end users who store files on the server to recover changed or deleted files without needing to contact an administrator or submit a support call. Shadow Copy works by automatically backing up documents and other data files (or even portions of files) whenever they're edited or changed in any way. The end-user UI isn't particularly discoverable, but once you know how it works, it can prove a godsend: Simply right-click on any file for which you'd like to access a previous version, choose Properties, and then access the Previous Versions tab to navigate through a list of the previous versions of the file that are available.

With Windows Vista, Microsoft has added this highly useful feature, finally, to its client-side operating system as well. Now known by the friendlier name Previous Versions, it allows end users to recover previous versions of documents, or even recover files that were accidentally deleted. Furthermore, Previous Versions works with the Windows Backup tool mentioned previously, so if Backup has automatically backed up a copy of a data file, Previous Versions will list that version as available as well.

This is an absolutely killer feature. Unfortunately, it's available only in the non-consumer versions of Windows Vista, including Vista Business, Enterprise, and Ultimate.

Encrypting File System (EFS)

Like previous NT-based versions of Windows, Windows Vista includes support for the Encrypting File System (EFS), which is really a feature of NTFS, the default Vista file system. EFS allows you to encrypt individual files or particular folders (and their contents, including files you add later), which will keep that information secure from thieves should your PC be stolen the hard drive is taken out and placed in a different PC. Files and folders that are encrypted are accessed seamlessly, on the fly, so to you, the end user, there is not perceived performance hit or special requirements. Note, however, that because of dangers inherent to encryption, you should back up your encryption keys as well as any data stored in this fashion. Otherwise, you could find yourself locked out of your own data files should your system fail in some fashion.

This feature is available only in the non-consumer versions of Windows Vista, including Vista Business, Enterprise, and Ultimate. This is comparable to the situation with Windows XP, where EFS was only available in XP Pro.

Power state transitions

In the previous part of this review, I mentioned the new power management states that Microsoft added to Windows Vista. It's worth noting here that these new states, and the way Windows transitions between them, will also increase the overall reliability of Windows Vista, because they will help prevent the so-called "burning briefcase" syndrome, where a user closes his laptop, assumes it's gone to sleep, and then pulls the burning hot device out of his briefcase hours later (perhaps on a plane), only to discover it never went to sleep and the battery is almost dead. This is a bit of functionality that Apple figured out long ago, and any inroads Microsoft can make in this direction are welcome indeed.

Curiously, however, I'm a bit gun shy thanks to my prior experiences. While I've found that Vista's power management state transitions are indeed far more reliable than they were in XP, I still babysit a notebook computer that's been closed to make sure it's really gone to sleep. Hopefully, a longer period of time with no mishaps will help regain my trust.

64-bit reliability features

While the 64-bit (x64) versions of Windows Vista draw a virtual line in the sand for a number of obsolete technologies (like the 16-bit MS-DOS and Windows subsystems), Microsoft is also using these versions to create a division of a different sort: x64 versions of Windows Vista are inherently more reliable than their 32-bit relations because of features and requirements that are unique to these products.

An obvious example is Kernel Patch Protection, or PatchGuard. This feature, available only on the x64 versions of Windows Vista, prevents programs from patching the Windows kernel at runtime. In today's Windows world, both hackers and security firms like McAfee and Symantec routinely patch, or modify, the kernel at runtime (presumably for completely different and opposite reasons). However, these hacks require undocumented and unsupported kernel hooks that could change in future releases, and they make the system more unreliable because the core code in the system now includes code not written or supported by Microsoft.

In Windows Vista, this practice has been abolished (though, after complaining from security firms, Microsoft has pledged to provide security firms with a way around PatchGuard protections by Vista Service Pack 1, in late 2007). Now, if Vista x64 versions detect any attempt to penetrate the kernel, the system will simply shutdown immediately. This may sound rather hard core, but if Vista were to take the time to blue screen and/or record what happened to disk, the kernel hack might have time to succeed.

64-bit versions of Windows Vista also require signed drivers, which helps prevent against many common causes of system crashes: Signed drivers tend to be of much higher quality than unsigned drivers. With signed drivers, Microsoft can more easily identify the causes of system crashes and work with the driver makers to fix problems.

Final thoughts

I've only scratched the surface of the new reliability features in Windows Vista, but as I'm sure you can see, there's a lot there. As with security, we'll need to see how Vista performs in the real world before we render a final verdict for overall reliability. But the early signs are quite positive indeed.

Next: Windows Vista Features: Internet Features.