Windows 98 build 1581.1

Windows 98 build 1581.1 is an interim build of Windows 98, which was originally shared on 11 September 1997 by the warez group SWAT.

Changes

 * Microsoft Chat is now installed by default.

System configuration
It is recommended to run this build in an emulator such as PCem or 86Box, otherwise you will encounter errors relating to Internet Explorer during the System Configuration portion of the setup. Should you encounter these errors, you must close them to continue, but note that many system applications will not work.