Fixes to Windows 98 to resolve the Year 2000 problem were distributed using Windows Update in December 1998.Microsoft attributed the sales success of Windows 98 in part to Windows Update.Initial releases of Windows 2000 shipped with the tool, but Windows 95 and Windows NT 4.0 were not supported.
It also narrowed down the list of available updates for the operating system and related components by sending details of what operating system version, service pack, and locale are installed.
German technology web site published an analysis of the Windows Update communication protocol in February 2003, which received wide attention on technology web sites.
If that one server got compromised one day, or an attacker cracks the MS DNS server again, there could be millions of users installing trojans every hour.
The scope of this attack is big enough to attract crackers who actually know what they are doing..." The Critical Update Notification tool continued to be promoted by Microsoft through 1999 and the first half of 2000.
With the release of Windows ME in 2000, Microsoft introduced Automatic Updates as a replacement for the Critical Update Notification tool.