Yea, yea, I know, below is a mess. It's just a quick-reference page for our techs.

Updated on March 12, 2008 - The August 2007 changes are shown in yellow.

The August  time zone updates apply only to the following time zones:
Caucasus Standard Time
Armenian Standard Time
New Zealand Standard Time
GTB Standard Time
Jordan Standard Time

August 2007 cumulative time zone update for Microsoft Windows operating systems - Updated info here.

The updates for XP/2003/Vista can be grabbed from Windows Update, or pulled from the following links:
For Windows XP w/SP2: Download details: Update for Windows XP SP2 (KB933360) (Replaces KB931836)
For XP and 2003 64-bit versions: Download details: Update for Windows Server 2003/XP x64 Editions (KB933360)
For Windows Server 2003 32-bit versions: Download details: Update for Windows Server 2003 (KB933360)
For Windows Vista: 32-bit version | 64-bit version
For Exchange 2003 w/SP2 (No need to update if already applied): Download details: Update for daylight saving time changes in 2007 for Exchange 2003 SP2 (KB 926666)
NOTE! Both Exchange 2000 and Windows 2000 are at EOL, so no "free" support patch is available, however they can be patched manually following the instructions further down.
The rest of the info below still applies, however it will not be updated as the August changes don't apply to any of our customers, unless requested  
For Win9x/ME: Unofficial DST Update for Windows 98/98 SP1/98 SE/ME [68 KB, English] (Not tested or supported by MicroTECH!!) At the end of installing this Unofficial DST update you MUST confirm your Time Zone selection: when you see Date/Time Properties you MUST click OK!
For Novell Products: Novell Time Zone and DST Changes for Novell Products
    In particular, NetWare v4.12 and higher: Daylight Saving Time Adjustment Tool for NetWare Servers
    Now it is possible to manually adjust this for v3.11 and v4.11 servers using the SET commands mentioned in that KB article, however we have not tried and tested this procedure as we only have such a small number of clients still using these old NetWare versions and they have not contacted us about this issue. I'm sure, however, we're gunna hear from them on Monday March 12. :-(
For IBM Servers: IBM Daylight Saving Time alert - United States - These are for the various IBM software and hardware like AIX, Lotus Notes/Domino, and the Remote Supervisor Adapter used in their servers.
For XP, XP w/SP1, and 2000 follow below:

LINK: How to configure daylight saving time for the United States in 2007
LINK: Daylight Saving Time Correction for Microsoft Office Outlook Calendars - Help desk guidelines

Files mentioned in the above KB article referring to pushing the fix via Group Policy: DST2007Update_Win2k.cmd, TZupdate.reg, and refreshTZinfo.vbs
NOTE: You MUST edit the cmd batch file to match the AD domain name, otherwise it will not work!
Here is the reg file needed to apply to Windows 2000 English Builds ONLY. These will NOT work on Win9x/ME or on any other language!
TZupdate.reg (updated 03-05-2007 also you will have to rename the extension from TXT to REG)  and tzedit.exe to check the settings.
Then you MUST change the time zone following these steps (I've tested this and confirmed that this HAS to be done, otherwise the time will not update itself).

1. Double-click on the clock in the system tray.
2. In the Date and Time Properties dialog box, click the Time Zone tab.
3. Click to select a different time zone than the one you updated, and then click Apply.
4. Click the time zone that you updated, and then click OK.

For further checking to see what you need to do, you can use this step-by-step wizard: Daylight Saving Time Help and Support Center

For Exchange-wide editing of mailboxes:
    How to address daylight saving time by using the Exchange Calendar Update Tool - Older article
    How to address daylight saving time by using the Exchange Calendar Update Tool - Updated article
     Found this to be a major PITA to use:

• Has to be a PC with Outlook 2003 installed.
• Can't being using multiple Outlook profiles using the "Pick a Profile to start with" option.
• NOT an Exchange server.
• NOT a PC with the Exchange System Management Tools installed.
• Have to fiddle with one of the INI files in the tool.
• You have to set up the admin account with Full Mailbox Access and Send As rights to all mailboxes (script provided).
• You have to install the Outlook tool below anyway.

So unless you REALLY need to go through all this pain, then use it. Otherwise if you have a small # of users that actually use the calendaring feature, then you can do it manually using the Outlook tool below following this procedure:

1. Set up your user account with the Full Mailbox Access and Send As rights to the mailbox you need to edit.
2. Create a new profile just for that one user.
3. Use the Outlook tool.
4. Remove the rights to the mailbox.
5. Repeat as needed, with the exception of having to create a new user. Just rename the username in the existing Exchange profile.

I tend to keep the spare user profile installed for migrating a mailbox to a PST file, or if I have to look into some issue with a mailbox.

Here is the tool for Outlook 2000, 2002/XP, 2003, and 2007 to update your mailbox's calendar items. Use this AFTER you have applied/checked on the time zone changes to the OS first as it reads the time zone info from the registry!:
    Download details: Microsoft Office Outlook Tool: Time Zone Data Update Tool for Microsoft Office Outlook
    Opps, forgot to add the article that this comes from:
    How to address the daylight saving time changes in 2007 by using the Time Zone Data Update Tool for Microsoft Office Outlook