It is difficult to give a definitive answer to the question as to whether XMaster will be suitable for developing any given application without knowing rather more about the application.

In general, however, XMaster is suitable for applications in which during each consultation a number of hypotheses are to be considered and by means of asking the user questions, evidence is established which will enable XMaster to indicate some of these hypotheses as possible and discount others as unlikely.

This is a process generally known as 'diagnosis', 'hypothesis selection' or 'hypothesis screening'.

In addition to specifying the hypotheses and items of evidence which the system must consider, it is also possible to define the following items:

Question text to be asked of the user in relation to each item of evidence;

Text which can be attached to each item of evidence which will usually give some insight into the reason for or the nature of that question;

Text which can be attached to each hypothesis which might typically be used to give further information or explanation or to suggest a course of action to the user in relation to that hypothesis.

An alternative terminology to be used in place of the default terminology of hypotheses and items of evidence. So, for instance, a knowledge base developed for medical diagnosis might use the alternative terminology diseases and symptoms; whereas a knowledge base developed for horticultural purposes might refer to plants and characteristics, or whatever terms you choose.

XMaster has been designed and tested only in English.

However, because of the unique nature of its graphical user interface you may find that XMaster also works well in other languages when used with the appropriate keyboard and language version of Windows.

This is because developing an expert system with XMaster largely involves filling in boxes with text of your own choosing and, as far as XMaster is concerned, this text can be in any language and in any alphabet you care to choose.

This flexibility is enhanced by XMaster Developer's Terminology option which allows you to choose your own terminology rather than simply use the default terminology of Hypotheses and Items of Evidence - and your own terminology can, of course, be in any language.

In addition to this, much of XMaster's working - whether developing or consulting an expert system - is done graphically and, as such, is largely language independent.

However, there do remain textual aspects of XMaster which remain in English - and that includes the manuals and Help system!

The most common reason for this is because you already have an application running on your machine which is interfering with the installation process.

Try quitting all other applications before you install XMaster.

Incidentally, this is generally true when you are installing software - it is not a problem that is unique to XMaster!

Try re-starting XMaster with the /LORES or /HIRES start-up parameters specified after the executable filename in the Windows Properties dialog box.

Also: try changing your display from Large Fonts to Small Fonts (or vice versa) by using the Windows option:

Start...Settings...Control Panel...Display...Settings...Advanced.

When adding command line parameters to any application program using the Windows Properties dialog box you have to leave a space between the name of the executable file (in this case XMASTER.EXE or XDEV.EXE) and the command line parameter so that Windows can tell the two items apart.

Almost certainly, you have entered into the target box a command line something like:

<path>XDEV.EXE/LORES

which Windows will interpret as a request for an executable of that (entire) name.

You should have entered:

<path>XDEV.EXE /LORES ie with a space after the .EXE

Alternatively, if you had simply omitted the forward slash, /, then XMaster will start but you will get a message saying it cannot find file LORES.XGN or some such; as, without the forward slash, XMaster interprets any command line parameter as being the filename of a knowledge base it is supposed to open on start up.

The thinking behind this is that you only need to be able to load XMaster Developer onto one machine in order to develop your knowledge base.

However, once you have developed that knowledge base, you will probably want to show it to other people - colleagues, customers, or friends, perhaps - so that they can access your handiwork.

To do this these people have to be able to install XMaster User onto their machines.

The XMaster Developer licence does not allow for completely royalty-free distribution of either XMaster Developer or XMaster User ; but it does allow you to make a reasonable number of copies of XMaster User - five, to be exact - without further licensing fees being payable.

The Which? Web Trader scheme was launched in 1999 by the UK Consumers' Association, publishers of the consumer magazine, Which?

The award was made to web traders only after careful vetting of their web sites by experts from the Consumers' Association in order to satisfy them that such sites met their criteria for the security and integrity needed for safe e-commerce.

Chris Naylor Research Ltd was one of the very first such firms to be awarded the Which? Web Trader logo which confirmed the high standards we apply to all aspects of e-commerce.

However, the Consumers Association terminated the scheme as of 31st January 2003 and all Which? Web Traders withdrew the logo from their web sites at that date.

This does not mean that our standards are any less exacting than they were. We will always continue to support the highest standards of e-commerce - just as we did before.