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XP is fundamentally different to previous desktop versions of Windows, but it can still crash and take your hard disk with it.
 Would you know what to do if your Windows XP machine went wrong? If you're not prepared, XP can spring some nasty surprises on you, even if you know how to recover from crashes with earlier versions of Windows. In the past you could use an emergency disk to reboot a damaged system, which would allow you to work in MSDos to repair the damage or even to reinstall the whole system. However, XP has no MSDos, so you have to handle a crashed system differently. The worst time to discover this is when your PC has just died and you're in the middle of a vital task, so read on and be prepared. XP is the first desktop Windows operating system not to be based on MSDos. You may not have realised this because you can still run Dos programs in the command-line console, but that isn't the same as being based on Dos. Windows 98 boots into MSDos and then loads Windows on top of that. Windows XP loads MSDos only if you try to run an MSDos program from the console. This is an important difference, because a common strategy that's used when Windows 98 goes wrong is to boot using an MSDos diskette, which gives you full access to the hard disk. This isn't quite so easy under XP as, like NT, it is supposed to be a secure system. It didn't really matter how many passwords you set on a Windows 98 system, if you had an MSDos boot disk you could get at the files. The same is true of Windows XP if you use the Fat or Fat32 filing system as opposed to NTFS. From a security point of view a Fat filing system is useless, although you may think it worth using so that you can boot using MSDos if things go wrong. However, NTFS is more efficient and more reliable as well as being more secure. Windows is also set up to treat NTFS as the default setup, and it can be difficult to choose Fat even if you want to. When you install XP it will ask if you want to convert the current disk from Fat to NTFS. You can also convert any Fat volume to NTFS using the Convert command-line utility, but there is no utility to convert to Fat, even if you reinstall XP. As far as Windows is concerned, it's a one-way process. If you boot an NTFS XP computer with an MSDos boot disk you can't access the data on an NTFS disk. So what can you do? Safe cracker You can control how Windows XP boots up by holding down the F8 key as your PC starts. The range of choices that you have include Safe Mode, Safe Mode with Networking and Safe Mode with Command Prompt. Safe Mode is a minimal graphical mode in which XP starts only the drivers that are really necessary, such as the mouse (not serial mouse), VGA, keyboard and IDE/PCI hardware. Safe Mode with Networking also loads the network drivers. Safe Mode with Command Prompt is very different; it starts a command prompt automatically and doesn't load some of the user interface processes. If the problem is in the video drivers or the video hardware, you could also try the 'Enable VGA Mode', which starts XP in the most basic video mode - and hence the one most likely to work - using a generic VGA driver. This video driver is used in all of the other Safe Modes, so if you can't start your machine in any of these you won't get it to work in VGA mode. If you can start your computer in one of the Safe Modes you can access most of the tools and do just about anything to solve a problem, as long as you know how. If the problem is simply a corrupt system file, XP will usually tell you the name of the problem file, and you can simply copy the file from the CD to the hard disk. However, if a driver is causing the system to fail, a better solution might be to 'roll back' the configuration to an earlier one that works. The simplest way to do this is to select the 'Last Known Good Configuration' from the list of startup modes. This always seems a bit magical because it's as if XP knows the last time it was working properly. In fact, it's very simple. Every time you shut XP down it records its configuration as the last one that worked. If you start it up and install a new driver, and that driver causes XP to crash before you shut XP down, the Last Known Good Configuration will be the one that doesn't include your new driver. This is the simplest way to recover the system from this sort of problem, but it can't solve file corruption problems and is useless if you manage to shut down the computer before the driver crashes your system. Restoration comedy You can roll back your machine to an earlier state without having to reboot. All you have to do is start the System Restore Wizard, which you can find in the Start Menu, Accessories,System tools. Once it's running you can create a restore point or restore your PC to the state it was in on a given date, as long as that date was a restore point. XP makes occasional restore points and usually creates one just before you install any new drivers. Dates that correspond to restore points are shown in bold, and clicking on them reveals a list of reasons why the restore point was created. When you restore to an earlier configuration, system files are restored and drivers and some applications are uninstalled. However, your personal files should be quite safe as restore doesn't do anything with data files, including emails. In theory all restores can be reversed, so if things go wrong you can undo them. In addition, a system restore doesn't uninstall an application completely; it leaves the application's files behind and removes only system file entries, making the application unavailable. You can control how much disk space the system restore uses and even turn it off completely. Console yourself How you go about recovering a problem system depends on how bad the problem is. If you can start the computer and use XP, you should use the System Restore utility. If you can't get XP running, try to use the Last Known Good Configuration option at startup. If those system files have become corrupt this will not work, and your next step is to try to boot into any of the Safe Modes and copy the problem files from the Windows XP CD-Rom. If you can't even get started in Safe Mode, it's time to turn to the Recovery Console. The Recovery Console is vital to sorting out problems with XP. This will be new to most Windows 98 users, but not to Windows NT or 2000 users. There are two ways to get to the Recovery Console. You can install it on to a hard disk so that you can boot to it, or you can use the original Windows XP CD to boot the system. In most cases it doesn't make much sense to put the Recovery Console on the hard disk, because if you have a serious problem you will not be able to boot from the hard disk anyway. However, if you want to install the Recovery Console as an option you have to put the Windows XP CD in the drive, click the Start button, select Run and enter 'D:\i386\ winnt32.exe/cmdcons'. Then you simply follow the onscreen instructions. The next time you boot your PC you will be given a choice of XP or the Recovery Console. Another, rarely mentioned, way of running the Recovery Console is to make XP boot disks. It takes six floppy disks to store all the files you need to boot XP, and you can get them only by downloading them from the Microsoft website. You can find the disks in the download centre at www.microsoft.com/downloads. Microsoft says that future versions of Windows will not support booting from floppy at all, so this procedure is on its way out. There are two setup programs: one for XP Home and one for XP Professional. When you download and run the relevant version it asks you for six blank floppies. Booting from these gives you the same range of choices as booting from the CD-Rom. Scanner in the works However you reach the Recovery Console, it works the same way. It scans the disk to locate any possible Windows XP installations and asks you to select the directory to work on. If you're not careful you might just hit Enter at this point, which simply reboots the system. Instead you have to type the number of the directory, even if there is only one in the list. You also have to supply an administrator password to gain access to the system. Any user who is a member of the administrator group can supply the password, and if no password was set you can simply press Return to enter a null password. You get three chances to get it right before the system reboots. If you supply a suitable password you are presented with what looks like a standard command console, but it isn't. The main difference is that you can use only the commands that are built into the Recovery Console. Some of these commands are very powerful, so be careful or you could do more harm than good. The Recovery Console lets you enable and disable services, format drives, copy files from the CD or floppy, delete files and generally change the system configuration. As all of this is done from a command prompt it often isn't easy. To find out which commands are available simply type 'help'; however, this doesn't give you much idea of what they do. If you remember anything about MSDos or the commands available at the command prompt you will already know what most of them do. However, many of the familiar MSDos commands that are available at the command prompt have a different range of parameters. Your word is my command The commands available include Attrib, which changes the attributes of a file or directory; Chdir, which changes the default directory; Cls, which clears the screen; and Copy, which copies a single file from one location to another. Delete (Del) deletes files, Dir displays a catalog of files, Exit restarts the system, Mkdir creates a directory, Rename renames a file, Rmdir deletes an empty directory and Type displays the contents of a file. These are the standard commands, but sometimes they don't work as you might expect. For example, the Copy and Delete commands will work only with a single file. You can't copy files to a floppy or any removable drive, but you can copy files from the removable drive. You can't do anything with files that are outside the system directory, which is usually C:\Windows. Call in the professionals Many Recovery Console users believe that these limitations are fixed and unchangeable, and for XP Home users they are. However, XP Professional provides greater flexibility for its users. They are controlled by a set of environment parameters that can be changed by the SET command. The environment parameters are: • AllowWildCards • AllowAllPaths • AllowRemovableMedia • NoCopyPrompt These are all set to 'false' by default in an attempt to make XP more secure. SET is also disabled by default, so you can't actually change anything. Even if SET were enabled, however, these four would be the only environment parameters you could modify. This is another security measure, but one that is difficult to change. The approach to take is to open the Control Panel, select Administrative Tools and open the Local Security Policy tool. Use the Security tree to navigate down to Local Policies,Security Options. You should find entries relating to the Recovery Console. To make SET work you need to enable 'Allow floppy copy and Access to all drives and folders'. After this you should be able to use SET to change the way things work. If you have XP Home, forget it. This version doesn't support security templates and there's no way of changing how the Recovery Console works. This is another example of how Microsoft has simply removed features from XP Home to make it less 'professional' than XP Professional without really thinking it through. Command performance Many of the less common commands are restricted in the same way by the inability to use wildcard characters or to copy files outside of the system directory. First there are the general-purpose helper commands: Batch runs a file of Recovery Console commands; Net Use lets you connect to a network device - provided you supply a username and password, of course - and Systemroot changes directory to the system root directory, usually C:\Windows. The Copy command is the main tool in restoring files to the hard disk unless they happen to be stored in a cabinet (.cab) file. These are files that hold several other compressed files. The Expand command copies and expands a .cab file. Other commands allow you to work with drivers and fix any faults you might find. Listsvc lists the services and drivers available on the computer. Disable/Enable disables or enables a service or driver. These changes are permanent, so if you disable a driver it will be disabled the next time you try a full restart of the system. Your strategy should be to do as little work as possible before getting the system running in Safe Mode, where you can fix things more effectively. Finally, there are some powerful commands that let you work with the hard disk. These are the commands you need to know if your machine is attacked by a virus or suffers a major hardware problem. Bootcfg allows you to edit the Bootcfg.ini file; Chkdsk checks the disk for bad blocks, cross-linked files and so on, and corrects disk problems; Diskpart creates and deletes partitions and is similar to FDisk in MSDos; Fixboot writes a new partition boot sector; Fixmbr repairs the Master Boot Record; Format formats a disk and lets you specify the type of file system; and Map returns a list of drive letter assignments. In a fix If you are having disk problems that require you to use any of these commands, you are likely to lose some, if not all, of your data. If the drive isn't booting or is not recognised at all, you need to try the Fixboot and Fixmbr commands. Be very careful, though, because the Fixmbr command can make a complete mess of any partitions already on the disk. You may need to use these if a virus has modified either boot record. Bootcfg is a much higher-level command and handles the configuration of how each operating system on the disk is treated at boot time. You can use this to debug and generally modify things such as multi-boot configurations. Obviously Diskpart and Format will both destroy your data, but they may restore a hard disk to a condition where it can be used again. Make sure you use the Map command to find out exactly which drive is which before you format using a drive letter. If you just have a general disk problem, use Chkdsk to see if it can be repaired to the point where the system boots in Safe Mode. Auto recovery There is an alternative to the Recovery Console, and at first sight it might seem to be a better option, but you have to remember to make recovery disks on a regular basis. If you are running Windows XP Home you have to install the backup program first. Go to \Valueadd\MFST\NTbacku and run the NTbackup program you find there. Once that's installed run Backup and select Advanced mode. There you will find an Automated System Recovery option. This will create a set of floppy disks that you can use to restore the system to its current state. To restore the system you boot from the CD-Rom and press F2 when the text screen asks what you want to do. You then feed in the diskettes and your system is restored to the saved state. However, data files are not restored or modified. 
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