One reader wanted to know how he could keep using now defunct file formats on his Windows XP PC. Our Helproom Editor explained how to open and edit older documents on a modern Windows PC and on a Mac.

QUESTION I want to be able to open and edit documents in old file formats – Lotus 1-2-3, Ami Pro and so on. Until my recent retirement, I was able to use a computer at work to achieve this. I'm now dependent on newer versions of Microsoft Office and WordPerfect, which don't seem to support these file types. I'm currently using Windows XP, but would like to replace my laptop with an Apple MacBook. Dick Harris

The best solution for keeping these legacy file formats alive is to use virtualisation software. It's a similar situation to the one detailed in the story: How to run GWBasic on a 64bit Windows PC.

You can continue to run old programs on a new PC by setting up a virtual machine. This allows you to run older applications within a virtual environment. Think of it as running one of the old office PCs on your home computer in virtual form.

To make this work, however, you would need to transfer the original programs over to the virtual PC. This may be tricky if legacy media such as floppy disks are to be used, and even more difficult if you don't have access to the original software.

A better long-term solution may be to convert the files into a newer format. This may be the most time-consuming option, since you'll need to find a converter for each type of file you wish to use. Of course, once you've converted the files you won't need to repeat the task.

As time goes on, converters that are compatible with the latest versions of modern applications become more difficult to find. For example, the Ami Pro converter that Microsoft provided for use with Word 2000 is no longer available for newer versions of Word.

And whereas older versions of Microsoft Excel supported the use of Lotus 1-2-3 .WK4 files, newer versions of Office do not. You may find you have to seek out versions of software that bridge the gap between your two chosen file formats.

In the case of Lotus 1-2-3, you will need a copy of Excel between version 7.0 and Excel 2003 to convert the .WK4 files to a format that can then be loaded into a modern version of Excel.

Alternatively, look for a copy of the latest version of Lotus SmartSuite. SmartSuite and Office 2003 can still be purchased from Amazon.

According to IBM's support site, Lotus SmartSuite will run on Windows 7, even though it was designed to be compatible only with Windows versions up to XP.

If alternative versions of these programs aren't available, conversion packages such as ABC Amber Lotus Converter can convert Lotus 1-2-3 files to an Excel-friendly format without either application needing to be installed on your computer. A demo version is available, but you must pay to unlock the software's full functionality.

Graham Mayor, a member of Microsoft's Most Valuable Professional team, runs a site containing free file converters for older formats.

An Ami Pro converter for Word is listed among those found on this site, including a version for Windows 7 64bit.

The move to Mac may mean that any Windows software will need to be run under emulation utilities such as Parallels Desktop, or you'll need to dual-boot Windows using Boot Camp. In either case, you'll need to buy a Windows licence. However, the number of conversion options available to you may actually increase, since you'll also be able to run Mac software that's incompatible with Windows operating systems.

Unfortunately, whichever method you choose, such file conversions are often rather irksome. Although you may get lucky in finding free converters for many file types, you may also find that certain features of the original format aren't supported. You will need to check that any documents you convert continue to function correctly. Finding a copy of the original software is the best way to ensure this.

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