This article describes an update that makes daylight saving time (DST) changes in Windows for Brazil and Morocco. Before you install this update, see the Prerequisites section.
This update applies to the following operating systems:
Windows Server 2016
Windows 10 (all except version 1507)
Windows Server 2012 R2
Windows RT 8.1
Windows Server 2012
Windows Server 2008 R2 Service Pack 1 (SP1)
Windows 7 SP1
Windows Server 2008 Service Pack 2 (SP2)
Windows Embedded POSReady 2009
Changes by location
Brazil is no longer observing daylight saving time (DST). Brazil was scheduled to start observing DST on the first Sunday in November (this year, on November 3), as described in the following Knowledge Base article:
4093753 Time zone and DST changes in Windows for Brazil, Morocco, and São Tomé and Príncipe
This change affects the E. South America Standard Time and Central Brazilian Standard Time time zones.
Fix: The base time for the "Morocco Standard Time" time zone in Windows did not update correctly to UTC+01:00 as expected in the Windows DST update that was installed on May 21, 2019 (KB 4501226). Instead, the system clock shows an incorrect base time of UTC+02:00.
This update resets the base time to UTC+01:00.
The update that is described in this article makes time zone changes in for the Brazil and Morocco.
For more information about how DST changes may affect other Microsoft products, go to the following Microsoft website:
For more information about how to configure DST settings in Windows, see the following article in the Microsoft Knowledge Base:
Note When you apply this update, you may receive a message that resembles the following:
Update cannot be installed as a newer or same time zone update has already been installed on the system.
This message indicates that either you have already applied the correct update or Windows Updates or Microsoft Update has automatically installed this update. No additional action is required to update the Windows operating system.