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Daylight Saving Time & Time Zone Blog
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Time zone updates for Brazil are available

Nakul_Bhagat's avatar
Nakul_Bhagat
Former Employee
Jul 16, 2019

The July 2019 update provides below changes for Brazil Daylight Savings Time (DST).

Brazil has decided to no longer follow DST. DST won’t start on the first Sunday of November 2019 as previously scheduled.
More details about latest DST changes for Brazil can be found here.

To reflect these changes automatically, Windows 10 customers should ensure they have the latest updates installed. Windows 10 Update history can be found here.

Updated Mar 31, 2023
Version 5.0

39 Comments

  • tzacchello's avatar
    tzacchello
    Copper Contributor

    Hello, Nakul_Bhagat.

    Same issues here. Like wdias-hcl and wellersonnascimento, the registry on Windows 10 computers has not changed after installing the latest cumulative updates.

    After patching a Windows Server 2008 R2 SP1 with the KB 4507704 I can see the registry changes, unlike Windows 10.

    Is that correct? Is there another way to validate the DST change?

     

     

    using

  • wdias-hcl's avatar
    wdias-hcl
    Copper Contributor
    Hi Nakul_Bhagat and sorry for the delay to respond...
    I have created a script here using the code provided by wellersonnascimento and I can see the same results...I also believe that the values for DaylightBias, DaylightDay, DaylightDayOfWeek and DaylightMonth should be 0.
     
    As a test, I used the TZEdit tool and unchecked the "Automatically set Daylight Saving Time" option which is still checked when using the tool....
    Then running the script again, I noticed that the values for that variables were changed to 0...
  •  @Win_DST,

    I have same problem as our friend @wdias-hcl. I identified the problem with the script below:

    Function DSTInformation
    {
    	Try
        {	
    		$ComputerName="$env:COMPUTERNAME"
    		$TimeZone = Get-WmiObject -Class Win32_TimeZone -ComputerName $ComputerName
    
    		  write-host("Caption = " + $TimeZone.Caption                        )
    		  write-host("Deion = " + $TimeZone.Deion                               )
    		  write-host("SettingID = " + $TimeZone.SettingID                       )
    		  write-host("Bias = " + $TimeZone.Bias                                 )
    		  write-host("DaylightBias = " + $TimeZone.DaylightBias                 )
    		  write-host("DaylightDay = " + $TimeZone.DaylightDay                   )
    		  write-host("DaylightDayOfWeek = " + $TimeZone.DaylightDayOfWeek       )
    		  write-host("DaylightHour = " + $TimeZone.DaylightHour                 )
    		  write-host("DaylightMillisecond = " + $TimeZone.DaylightMillisecond   )
    		  write-host("DaylightMinute = " + $TimeZone.DaylightMinute            )
    		  write-host("DaylightMonth = " + $TimeZone.DaylightMonth               )
    		  write-host("DaylightName = " + $TimeZone.DaylightName                 )
    		  write-host("DaylightSecond = " + $TimeZone.DaylightSecond             )
    		  write-host("DaylightYear = " + $TimeZone.DaylightYear                 )
    		  write-host("StandardBias = " + $TimeZone.StandardBias                 )
    		  write-host("StandardDay = " + $TimeZone.StandardDay                   )
    		  write-host("StandardDayOfWeek = " + $TimeZone.StandardDayOfWeek       )
    		  write-host("StandardHour = " + $TimeZone.StandardHour                 )
    		  write-host("StandardMillisecond = " + $TimeZone.StandardMillisecond   )
    		  write-host("StandardMinute = " + $TimeZone.StandardMinute             )
    		  write-host("StandardMonth = " + $TimeZone.StandardMonth               )
    		  write-host("StandardName = " + $TimeZone.StandardName                 )
    		  write-host("StandardSecond = " + $TimeZone.StandardSecond             )
    		  write-host("StandardYear = " + $TimeZone.StandardYear                 )
    	}
       Catch
        {
         Write-Warning "$Computer threw an exception"
         $Error[0].Exception.Message
        }
    	
    }
    
    DSTInformation

    As there is no daylight saving time in Brazil this year, I believe that DaylightBias, DaylightDay, DaylightDayOfWeek and DaylightMonth should be 0.

  • wdias-hcl, I don't know what and how the third-party tool (TZEdit) is reading datetime settings. However, can you confirm if you are able to see the proper value of DST offset for Brazil under datetime settings? Or are you suggesting it is off by 1 hour? If so, it is off by +1 hr. or -1 hr. ?

  • wdias-hcl's avatar
    wdias-hcl
    Copper Contributor

    Hi guys and Nakul_Bhagat !!

     

    I'm doing some tests here, looking for possible issues due to the DST change this year and I noticed the following behavior on Windows 10 machines.

    After install the latest updates, when I go to "Windows Settings >> Turn daylight Saving Time on or off", the option "adjust for dayllight saving time automatically" is disabled and greyed out....So given this info, I suppose that it was everything fine.

     

    However I see 1 hour time difference when using calendar in some programs...then I used the TZEdit tool to check and using this program, the DST is still option is still checked...no matter if using the regular or the dynamic option...follow some screenshots showing what I'm talking about:

     

    I thought that by updating the OS, these settings I can see still marked using TZEdit would also be unchecked...Because when I uncheck them using TZEdit tool, the 1 hour time difference is solved on calendar from other programs installed on the machine...

    - regular setting is marked when using TZEdit tool:

    - dynamic setting is also marked when using TZEdit tool:

    anybody else noticed similar behavior/problem?

     

     

  • Yuri_Costa's avatar
    Yuri_Costa
    Copper Contributor

    Hi, i´m having trouble in install cumulative update 7/16 Windows 10 1607 by WSUS in my company.

     

    I´m checking this trouble, but there is some specific KB for updates daylight in Brazil ?

     

    Thanks.

     

     

     

     

     

  • kbruno89 , the DST updates for Win10 are available as part of the cumulative update which was released on 7/16 for all versions of Win10 except 1809. For Win 10 version 1809, the update was released on 7/22. Thanks!

  • kbruno89's avatar
    kbruno89
    Copper Contributor
    Hi, Found KB (https://www.catalog.update.microsoft.com/search.aspx?q=kb4507704) for update in some versions of Windows, except Windows 10. Which exactly KB for update in Win10? Note: Enterprise enviroment.