I downloaded Kaspersky anti-virus software but had problems running it. Now I can't delete it from my system because I always get a message saying 'msiexec.exe has encountered a problem and needs to close'. Help. Mario Gaudette, Kowloon DQ: This sort of thing is a well-defined 'chicken and egg' problem: if you already have a virus, how do you download something to fix it? I have no idea if your machine is infected but that could explain what is going on. Reboot your machine and make certain anything that is automatically loaded at boot time is shut down. Go to the Kaspersky Lab website ( www.kaspersky.com ), which will allow you to run an application to scan your machine. If all goes well, you should be able to remove the software you downloaded earlier. Remember to load all the security updates from Microsoft. Sadly, that process may not fix everything. In that case, the only solution may be to reinstall your computer's operating system. But before doing that, take the computer back to where you bought it and see if the staff can help. This is one good reason to establish a positive relationship with your computer vendor, who will usually take care of such problems for you. I use a Windows XP-based Sony Vaio and want to upgrade to a bigger hard disk. But first I want to clone all the programs, including the ones set up by my office in Britain, and settings onto a portable hard disk. How can I do this? Nick Peake, Ho Man Tin DQ: Whenever you buy or download software, always save the installation package. Back it up and make a note of any serial number you may need. Always divide data from applications. If all your applications are on drive 'C', for example, then make certain all your documents, databases, spreadsheets, pictures, music and other files are on a different drive (or a different partition). Back up your data separately from your applications. If you have done all of that, changing the hard disk should not be a problem. Talk to your colleagues in Britain and see if they can put you in touch with a technical person who understands the software they had you download before. It should be possible to kill what you have then reinstall it. (I have software on my computer that allows me to register it on two machines. I can also 'deregister' it if I want to move it to another machine.) It is likely to be time-consuming but with companies establishing so many locks to prevent people from illegally copying software, you don't have much choice.