Q: I have bought a new computer running Windows XP. How do I transfer Windows Word and Excel from my old computer which runs Windows 98 to the new one?

A. In almost every case, all programs need to be completely reinstalled onto another computer from the original CDs and cannot be simply copied across. It will definitely fail for Word and Excel.

The reason why just copying files will not work is because during installation of most current programs, some files are written to the \Windows\System or \Windows \System32 as well as to other folders within Windows. As well as this, there will be entries in the registry that are usually essential for the program to run.

Your data files, such as the Word documents and spreadsheets, can then be copied to the appropriate folders after the installation is completed. The actual method of copying data files can be using the internet, using the network cable, via a CD or a USB drive.

If you do not have one and want to buy one, first ensure that the Windows 98 computer has a USB port and then ensure that the USB drive comes with a CD, as Windows 98 requires a driver to make this work while XP does not.

Q. I have just discovered in my "Documents and Settings" folder a file named Backup.pst. A search on the Microsoft Site advises that it is an Outlook settings and mail file. As it is using up about 8 MB of memory, naturally I would like to delete it. I do not use Outlook as I use Outlook Express. Can I safely delete this file or is it essential?

A. This is not an essential file, as this is a back-up of all your mail and is created when you export your mail. You are correct in that it is not used by Outlook Express but only by Outlook and therefore it can be deleted. If you examine the creation date of the back-up file it should give more information about how old it is.

Note that deleting it will not speed up your computer but only free up 8 MB of disk space and not memory. Removing it will not free up any memory, as this file just remains on the hard disk and will not be loaded into memory unless you open Outlook and open that specific file. 

Q: Recently I downloaded one of these free registry cleaners. It told me that I had 165 errors in my registry. Could you tell me a good cleaner and where I can buy it as I don't want to give my credit card number over the internet?

A. A few hundred errors in a typical registry that has 500,000+ entries is of no concern. These errors probably refer to programs that have been removed and most likely will not cause any problems.

Some free registry analysing programs give these potentially alarming reports hoping you will buy their product. If your system is stable, I would not buy a registry cleaner program.

Also, there is a small risk that a registry cleaner program may cause problems that at present do not exist. Microsoft had a free registry cleaner program but it was removed from their website some years ago without any reason given.

It could be that even Microsoft cannot give a 100 per cent guarantee that it works perfectly in all situations. In their knowledge base there is an article referring to a problem caused by one particular registry cleaner that prevented Windows from starting and reference to erroneous listing generated by other programs. Having given a lot of reasons why you should not buy a registry cleaner, I ran one on my test computer after it reported several hundred errors. I checked several dozen manually to find they were all referring to either removed or obsolete programs.

My registry file was about 70 MB when exported and came to more than 12,000 pages of text when opened in Word. After running the program it stated that all problems were fixed. Running benchmarks before and after showed no difference in performance and the size of the registry was reduced by a small fraction of 1 per cent. In the case of registry cleaners, I would apply the old saying, "If it ain't broke, don't fix it" but I am happy to hear other views.