On April 8, Microsoft stopped supporting Windows XP and Office. After that date there will be no new security updates, non-security hot-fixes, free or paid assisted support options, or on-line technical content updates. However, all your software will continue to work just as well as it did on April 7, so you needn't panic, but it would be prudent to come up with a rational transition plan. There are three choices: (1) continue to use XP, but take some precautions, (2) keep your present hardware, but upgrade the software, and (3) purchase new hardware and software. The hardware and software vendors as well as the media in which they advertise prefer that you take the third approach, but let's consider all of them.

There are many advantages to staying with XP, which may not hold with the other two approaches.

• Your present hardware works with it.
• Your present applications run under it.
• It supports your present peripherals.
• You don't have to learn anything new.
• It costs less than the alternatives.

The main disadvantage is that as time goes on, you become increasingly more vulnerable to attack over the Internet and by malware. You can reduce this and its consequences by the following.

• Before April 8,. use Microsoft Update to install the latest patches to all your Microsoft software.
• Update all your anti-malware software, and check that the vendor will continue to support it for XP after April 8. If not, change to a vendor that will.
• If you are connected to the Internet through a router, install the latest firmware in it. If your PC connects directly to your ISP's modem, purchase a hardware router, and update its firmware if necessary. For good measure, if you haven't already, install a software XP firewall.
• Be very careful about what you download, and avoid doing it if possible.
• Review you backup program; improve it if needed, and resolve to follow it rigorously.

The wording on the MS Website implies that old patches will remain available, but why take a chance? Update your software early, as the download rate may slow near the deadline. At the present time, about 35 per cent of the computers in the world use XP. This is a sizable market for anti-malware vendors, and I would expect them to continue supporting XP for some time. Your first line of defense against Internet aggression is your router and its firewall. Most likely, your ISP's modem also includes a firewall, but how careful is he about keeping it up-to-date? You don't know. With your own router, you have ability to keep it up to date, and as a result, having one is desirable even if you have only one PC. Despite all your precautions, as time goes on, and the bad guys find more XP vulnerabilities, your risk will increase. Be wary of any download, including e-mail attachments from friends. The best malware defense is to keep it off your PC. Your last defense is your backup program. Any information you haven't backed up on an external drive is one mouse click or one device failure away from trash. Although its most important to back up your data, you should in addition make an image backup of everything on your hard disk, because once XP becomes an orphan, applications and drivers for it will become increasingly difficult to find.

The second alternative is to keep your hardware, but change your operating system.

• Your vulnerability will be less than if you stay with XP.
• If your PC is old, it may not support some current operating systems.
• Your present applications may not run under the new OS.
• Drivers may not be available for some of your peripherals, requiring you to replace the devices.
• You will have to take care during the transition not to lose any data.
• You will have to learn new ways of working.

The hazard with this approach is that to install a new operating system, you generally must format your hard disk, but you must first inure that all your data is safe and readable by the applications in your new OS. For example, if all your financial records are stored in Quicken files and there is no financial program available in your new operating system that can understand them, you essentially have lost all your financial records. A second problem is to insure that your current hardware supports the new operating system before you format your disk. If you are considering a newer version of Windows, run the Windows Upgrade Advisor. Don't forget to check your peripherals; I found that there was no Windows 7 driver for my scanner and had to buy a new one when I upgraded from XP. If your PC is compatible except for insufficient RAM, this is an inexpensive upgrade, even if done by a shop. (You should have at least one Gigabyte of RAM, even if you stay with XP.)

Consider Linux, especially for a secondary PC. I've converted two XP machines to Xubuntu, which is more responsive than XP on old hardware. It has the advantage that you can try it out with a “live-CD,” which is bootable from a CD drive. It will be slow in this mode, but since it doesn't make any changes to the hard disk, you are just a reboot away from XP. While running Xubuntu, all the files on your hard disk are available, so you can check whether Linux applications can read them. (Instructions on how to create a live CD or DVD in Windows) If you have room on your disk or can add a second one, consider a dual-boot system in which you can run either system. (All your Windows files will be accessible in Linux, and Windows applications are available that can read Linux disk partitions.) However, Linux is not Windows, which means there are many differences between the two systems. Try to find a sympathetic, experienced Linux user to help you get started, especially if you are less than comfortable in adventure mode.

The third alternative, buying new hardware and software is the easy and safe, but expensive. You are probably best off to purchase new components. XP-era processors, RAM, displays, and hard disks are woefully inadequate for any current OS. Keyboards and mice now cost just a few dollars, and your old ones may use obsolete connectors. You can keep your printer and scanner if drivers are available for the new OS; your old speakers will be fine.

• Your old PC with your data, applications, and peripherals remains available for use.
• You will probably have to purchase new applications for your new OS and probably some new peripherals, especially if the existing ones are several years old.
• There will be a learning curve for the new system.

Spend some extra money; in particular, get more RAM and a larger disk than you think you can get by with.

I haven't considered a piecemeal hardware upgrade, because I don't think it's cost-effective. Most modern CPUs are incompatible with XP-era motherboards; new motherboards are usually incompatible with XP-era cases and expansion cards; and old RAM is incompatible with both modern CPUs and motherboards. My preference is to get a new PC up and running with all the essential software installed, and keep the old PC operating until you are comfortable with the new one and are sure that it has all the applications you need and that all your data has been successfully transferred to it.