Beginning on January 1, 2019, new Avast Antivirus products will no longer be delivered for the Windows XP and Windows Vista operating systems. As customer demand grows for Windows products for Windows 7 and other new versions, demand for products that support Windows XP and Vista decreases. In order to receive new feature releases of the Avast antivirus software, users will be required to update their Windows operating system.
This means that as of January 2019, existing users on the Windows XP or Windows Vista OS will remain on version 18 or older rather than migrating to version 19.1 scheduled to be released in January of 2019. However, please note that all Windows XP and Vista users will continue to receive virus definitions updates from the Avast Threat Labs database after this date and Avast Antivirus versions 18 and older will continue to work as usual providing full protection, but will not receive regular automatic updates of new program versions with new features.