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New Member

Daylight Saving Time change in 2007

Has anyone looks into the Daylight Saving Time change that will go into effect in 2007 ? I understand that DST will start 3 weeks earlier and end one week later in 2007.

I understand that we need to change the DST in Windows but does anyone know if there is anything special in Unity or Exchange that we need to do ?

Thanks !!


Cisco Employee

Re: Daylight Saving Time change in 2007

Hi Danny,

I think I have at least a partial answer to your questions: I have found out that there will soon (not sure exactly when) be a comprehensive Field Notice posted soon concerning

Preparing for daylight saving time changes in 2007" on Cisco Unified Communications

servers, including Unity.

If you go to this web page:

Product Field Notice Summary


You can set up the Product Alert Tool to send you a notification to you whenever there is a new Field Notice.

So, to answer your question about Unity. For Unity running on a Windows 2000 server, the

procedure is to manually update using the tzedit.exe utility or other techniques

documented in Knowledge Base article 914387 and similar articles for other countries, which is the preferred method of remediation for any product outside of Mainstream Support.

(The tzedit.exe tool allows you to create and edit time zone entries for the Date/Time

settings in the Control Panel, especially for daylight-saving time).

Knowledge Base article 914387 "How to configure daylight saving time for the United States in 2007"

The tzedit.exe tool can be downloaded from a link within the link above.

I hope this helps.

New Member

Re: Daylight Saving Time change in 2007


Can you tell me if there is anything that I need to do on the Exchange 2k message store ?

I appreciate your response !! Thanks !!


Re: Daylight Saving Time change in 2007

Hi Danny -

This Microsoft article discusses Exchange and the DST update -

Collaboration Data Objects (CDO)-based programs such as Outlook Web Access depend on separate internal time zone tables.

I doubt this update would be needed for voicemail only configurations, but I would confirm with Cisco first.


New Member

Re: Daylight Saving Time change in 2007

Hi Ginger ! I appreciate your response I always get good feedback from your responses.

So as long as we get the Windows OS updated to the new DST by running the tzedit.exe tool from MS on both the Unity server and the Exchange server and that should all we need to do correct ?

Thanks Ginger !!


New Member

Re: Daylight Saving Time change in 2007

I understand Tzedit.exe is Microsoft's utility for the DST change. However I only see this applying to standalone VM running it's own clock.

Since UM is taking the clock off the windows time service on the AD Domain wouldn't it's time be changed regardless of the local settings?


New Member

Re: Daylight Saving Time change in 2007

Nope. SNTP doesn't dish out timezone information. That is calculated on the local machine using the timezone offset database. RFC 1769, 1305.

Windows time is fully compliant with SNTP so I assume the above is correct.

New Member

Re: Daylight Saving Time change in 2007

I noticed this morning states that Unity is still "Under Investigation".