I have tried to upgrade to Skype 4.0 on Windows but it doesn't work because the 'add or remove programs' function will not uninstall the older version of the software. Any ideas? Tony, Hung Hom DQ: The add/remove function of Windows is extreme-ly useful if you're the type who downloads and tries out free software. But some software needs to be uninstalled another way. In such cases, applications need to be removed manually using the registry key displaying the program in the 'currently installed programs' list. Microsoft's help and support site provides a detailed 10-step approach for this. The list (support.microsoft.com/kb/314481) tells you how to modify the program registry. However, be careful as serious problems might occur if you follow the steps incorrectly. Back up the registry before modifying it. There are also a number of free programs for this. These include Revo Uninstaller (www. revouninstaller.com); Absolute Uninstaller ( www.glarysoft.com ); MyUninstaller ( www.nirsoft.net ); Safarp ( http://wistinga.online.fr/safarp ) and CCleaner ( www.ccleaner.com ). I recently switched from a Windows PC to a Mac. Everything works except for the slightly irritating Chinese input. Can you help? Name and address supplied DQ: There was a time when Apple's Macintosh operating system was a lot better at multilingual computing but it dropped the ball a few years ago. The advent of Unicode, an industry standard to represent the characters of all the languages in the world, has allowed other platforms to catch up. I have been using QIM, short for Quickcore Input Method, which is a Chinese-language input method running on the Mac OS X platform. This solution is not from Apple but it offers a vastly enhanced user experience. One excellent QIM design allows users to hit 'caps lock' while in Chinese input mode to switch back to English. This is a great feature because it can be a real pain to navigate through all the functions on the Mac system. QIM's greatest ability is enabling a user to write entire sentences in pinyin that are converted on the fly. The software costs US$19.99 from glider.ismac.cn/RegQIME.html. You can type up to 10,000 characters before the program asks for payment.