Microsoft announced two dates recently that Windows users should heed.

On April 13, Microsoft will no longer support Windows Vista that has no service packs installed.

Second and more importantly, on July 13, support will end for all versions of Windows 2000 and all version of Windows XP with Service Pack 1 and Service Pack 2.

End of support means that Microsoft will no longer give phone and e-mail technical support and will no longer fix bugs and issue security patches.

Before XP users go off the deep end, many installed Service Pack 3 for XP some time after its release in 2008. Even if you install it now, your support will continue.

If you do nothing in any of these cases, your computer will continue to run, and you probably won't be able to tell the difference.

However, if support lapses and Microsoft never issues any more security fixes, you are laying yourself open to attack.

How do you tell whether you have Service Pack 3 for XP? Click the Start button, click Run and type "winver" in the resulting box. Click OK and the information should appear. Another way is Start: Settings: Control Panel: System: General tab. If Service Pack 3 shows up there, end of immediate worries.

If you do not have Service Pack 3, you have two choices. You can upgrade to Windows 7, which costs money (about $120), and though it is sold as an upgrade, is really a "clean" install. (More on that later.)

TechMan recommends this if you can manage it because Windows 7 is a good operating system and is much more secure than Windows XP.

If you want to stick with XP, you should install Service Pack 3 if you don't have it. Go to windows.microsoft.com/en-US/windows/help/windows-xp and click on Windows XP Service Pack 3 at the left.

After you've installed Service Pack 3, how long will you have before Microsoft drops support for it?

That gets into Microsoft's support lifecycle policy, which determines how long the company will support its products. In general Microsoft provides support for five years after the release of a product or two years after the release of a sucessor product, whichever is longer.

But there also is a support policy for service packs. Windows XP Service Pack 3 was released in May of 2006. According to Microsoft's policy, a service pack will be supported for two years after the next service pack is released. The problem is that there won't be a Service Pack 4 for XP. Therefore the support for Service Pack 3 will end when support for Windows XP ends.

Under Microsoft's policy, support for Windows XP, which came out in 2001, could have ended in 2006 or 2009, But obviously that is not happening. Instead Microsoft has said that on April 8, 2014, all Windows XP support, including security updates and security-related hotfixes, will be terminated. That's 13 years of security updates for Windows XP. Not bad.

If you are still running Windows XP in 2014, you should be ashamed of yourself.

For Windows 2000 users: Give it up -- upgrade now to Windows 7.

For users of Windows Vista with no service packs, it you are happy with Vista, install Service Pack 2.

Complete instructions for installing Service Pack 2 for Windows Vista are available at support.microsoft.com/kb/935791/.

In all cases above, TechMan's advice is to upgrade to Windows 7 if you can afford it. From Windows Vista it is a pretty simple upgrade. From XP you will have to do a "clean" install, which involves backing up your data, wiping your hard drive, then restoring your data, settings and applications. (That requires the original application install disks.)

Instructions for this are at windows.microsoft.com/en-US/windows7/help/ upgrading-from-windows-xp-to-windows-7.

Or the easiest of all is to buy a new computer with Windows 7 pre-installed.

And that, of course, is just what the PC makers want you to do.

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