We have received reports that Armenia and Ukraine have canceled their proposed changes. According to reports in Rada and Kyivpost, Ukraine will not stay on permanent summer time and instead will fall back to winter time on October 30, 2011 as originally scheduled. If these reports become the plan of record, customers in Armenia and Ukraine will not have to adjust time zone settings on their computers that are running Windows. This Microsoft Knowledge Base article will be updated when Microsoft has confirmation about this decision.
Time information in Windows for time zones in Ukraine [(UTC+02:00) Helsinki, Kyiv, Riga, Sofia, Tallinn, Vilnius], Belarus [(UTC+02:00) Minsk], and Armenia [(UTC+04:00) Yerevan] will be incorrect after October 30, 2011.
Ukraine, Belarus, and Armenia have decided to discontinue daylight saving time in 2011. According to the current Windows time zone rules, daylight saving time (summer time) is (UTC+3:00) in Belarus and Ukraine and (UTC+5:00) in Armenia. Summer time is scheduled to end on October 30, 2011 and move to winter time, which is (UTC+2:00) in Belarus and Ukraine and (UTC+4:00) in Armenia. According to the latest changes, they will remain on summer time (UTC +3:00) indefinitely and will not "fall back" to winter time.
The native time zones for the affected countries will be updated in the next planned cumulative Windows time update in December 2011. No hotfix is planned for release in the interim. Users in these time zones should move to the following alternative suggested time zones:
Windows 7 Service Pack 1, Windows Vista Service Pack 2, Microsoft Windows XP Service Pack 3, Windows Server 2008 R2 Service Pack 1, Windows Server 2008 Service Pack 2, Microsoft Windows Server 2003 Service Pack 2, Windows Embedded Standard 7