Part of Windows 98 Service Pack 1, this update corrects several minor issues associated with generating dates on your computer on or after January 1, 2000, including leap year calculations in particular circumstances, entering expiration dates in Microsoft Wallet, handling of some date/time settings, and correct logging of online calling. This update is only one component of the Windows 98 Service Pack 1 Note: Because the Windows 98 Year 2000 Update updates your system files, it is recommended that you disable any antivirus software that is running. If you chose not to disable this software, please accept the changes made to the IO.sys file when prompted by the antivirus software during installation of the update or after restarting your machine. It is also recommended that you create a new emergency startup disk after installing this update.