A method of updating computer software includes downloading software update information through a network, such as the Internet, to a user's computer. The download is preferably done periodically and automatically. If available, a criticality check program identified in the software update information is then automatically downloaded and executed to determine the configuration of the user's computer. The criticality and applicability of available software updates are evaluated by the criticality check program in light of the specific software and/or hardware configuration of the user's computer. The software updates may then be downloaded and installed automatically, if previously authorized by the user, by comparing the criticality of the updates to the user, as determined by the criticality check program, to stored user preference information specifying a user criticality threshold. Software updates determined to be more critical than the user criticality threshold are installed automatically and the user is notified of the availability of less critical updates.