Chris De Herrera's Windows CE Website

Discuss.Pocket PC FAQ Forum

Add Pocket PC FAQ to your Favorites
RSS    RSS Feeds
Wiki    Lost?
Custom Search
Subscribe    Print
Table of Contents
Mobile Format

[an error occurred while processing this directive]

Pocket PC Magazine Best Site

Website Awards
Website Updates

By Chris De Herrera 
Copyright 1998-2007
 All Rights Reserved
A member of the Talksites Family of Websites

Windows and Windows CE are trademarks of Microsoft
and are used
under license from owner.
CEWindows.NET is not
associated with Microsoft 

All Trademarks are owned
by their respective companies.

Daylight Savings Time Patch
By Chris De Herrera, Copyright 2010
 Version 1.00  Revised 3/5/10

[an error occurred while processing this directive]


When you get a new Windows Mobile device, you expect that it is up to date with the latest patches.  Well unfortunately that may not be true.  Microsoft did not include the latest Daylight Savings Time update in Windows Mobile 6.5. 

Of course if you have an older Windows Mobile device (including Windows Mobile 5,0, 6.0, or 6.1) you need to install this daylight savings time patch as well.

Impact of Failure to Patch

If you fail to patch your device, you will see some peculiar issues.  In particular you will notice that all new appointments will be off by an hour on your device.  If you adjust the time on your device, you may notice that the time automatically changes back to the original time because Windows Mobile is able to set the time based on the cellular network's time.  If you disable the time updates on your device, you will see that all appointments are off by an hour when you sync on your PC.


If you synchronize your Windows Mobile Device with your PC using ActiveSync or Windows Mobile Device Center, you need to ensure that you have the latest updates installed on your PC.  The critical daylight savings time updates include the update for Windows XP, Windows Vista or Windows 7 as well as Outlook.

If you are using Windows Update, you will not automatically get any Outlook patches.  Consider switching to Microsoft update which updates all Microsoft applications installed on your PC.


When you install the daylight savings time patch on your Windows Mobile Device, don't forget to soft reset your device.  If you don't then the new settings will not take effect.

Resources at Microsoft

Windows Mobile DST Patch

Outlook Time Zone Data Update Tool

Daylight Savings Time Help and Support Center

HTC Recommended Fix

If your calendar appointments are showing up as an hour earlier after March 14, this is because of Daylight Savings Time, as you have stated. The reason why your calendar is changing the times of your appointments is because it is viewing daylight savings time on the 14th as a time zone change. Which means that after the 14th all of your appointments will spring ahead to the correct time. However, if you would like to resolve this issue as of right now you can follow these steps:

1. One the Home screen, slide over to the Settings tab,
2. Select All Settings
3. Tap on Clocks and Alarms
4. Change the Home time to GMT 0 Greenwich Mean time.
5. Synchronize your phone to either your computer or exchange server, depending on which you are using.
6. Then change the time back to the correct time zone
7. Synchronize your phone again.

Your issue should now be resolved for all items that you add into your calendar now, you may have to go back and adjust the old appointments. This issue is caused when you synchronize your phone to your computer or an exchange server. This issue should not preset after March 14th, but if you experience the issue again, please follow the steps above.


Once you have patched your PC and Windows Mobile device, Daylight Savings Time will be a non-event.

[an error occurred while processing this directive]

Return to Chris De Herrera's Windows CE Website