Time zone updates for Brazil are available

Robby_Chedie, for Windows 7 and so on, except by W10, we have the https://www.catalog.update.microsoft.com/search.aspx?q=kb4507704 as stated in the first https://support.microsoft.com/en-us/help/4507704/dst-changes-in-windows-for-brazil-and-morocco from Nakul_Bhagat original post. For Windows 10 we have some cumulative updates from July that should solve the issue. Since I couldn't find a better way to identify if those updates where installed or not in my users PCs, I cannot help you with that...

wdias-hcl, I'm not sure about what you didn't hear... my workaround perharps? If so, I didn't heard about it before, I just made it happen by trial and error after reading about how Outlook calculates the time for its calendar events.

Hi sorry I do not have the KB for the new fix but we need an new fix from Microsoft urgently.

This issue is causing chaos for our Brazil users especially when sending out Outlook meeting invites.

Robby

I didn't hear anything about it and I'm thinking why MS does not inform us here??

Robby_Chedie 

And do you have the KB number from this new fix?

Hi Daniel, thank you so much for the workaround. Do you know there is a new patch from Microsoft to resolve this for both Windows 7 and Windows 10 ? 

Hello everybody,

For those who have issues regarding out DST changes in Brazil, I've a workaround until you/we all manage to get the right updates in our Windows 10 machines.

First, lets talk about checking our DST settings:

w32tm /tz

Running W32Time with the parameter /tz give us an outpout showing the Standard Name for the Time Zone settings current in use, as well as the Month, Day and Day of the Week for the Standard time settings. It also shows the Daylight Name and its Month, Day and Day of the Week.

For us, brazilian users, our machines should show (M:1 D:1 DoW:2) for the Brazilian DST as in the image below:

*The PowerShell script from wellersonnascimento provide us more details for this settings if you run it.

In a machine without the proper updates regarding our DST settings, the line about the Brazilian DST will show values like (M:11 D:1 DoW:6).

Now, about the workaround:

In the Windows registry, look for the entry [ HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Time Zones\E. South America Standard Time\Dynamic DST ].

There we should see something like this:

And for one key up in the tree:

Both images were taken from a computer running Windows 10 with the proper DST settings. Any software that depends on the W10 DST settings and its registry entries should be fine with its time calculations, like Outlook for instance. *Check this link for a more detailed view of how Outlook handles it:
https://support.microsoft.com/en-us/help/2642044/how-time-zone-normalization-works-in-microsoft-outlook

Exporting the key E. South America Standard Time and importing it in a computer with the wrong settings is halfway there. After importing the key we should run w32tm /resync to "resync" the Time Zone settings, as the command suggests.

This workaround will work well until the affected machine receives any Windows Update containing the old DST settings. What did happen in some 1803 builds in my company... and I had to reapply the workaround until we properly updated every single machine.

* In the Outlook link that I gave you, there is no mention about how it reacts regarding the DST settings on our Exchange servers.

If anyone needs it, here goes a .reg file with all key/values we need:

I hope to be of help!

Best Regards,
Daniel Lima

brunok89 I think I have GPO privilegy! I execute the "tzutil" command with administrator profile. 

Here, the setting has remained.  saviski 

Do you have GPO?

Can be GPO overwriting?

Thank you brunok89! Almost solve. When I execute the command works well, but when I restart windows the DST flag come back to checked. 

tks

Edson