Be ready for 2007 changes to Daylight Savings Time

In 2005, the US Congress passed legislation to lengthen Daylight Savings Time. Starting in 2007, DST dates in the US and Canada will start three weeks earlier and end one week later. This obviously impacts many software products, including several from Microsoft. Does it affect yours? What do you need to do about it?

For starters, understand how Microsoft is responding to these changes by visiting, which will be updated regularly.

Next, consider attending a webcast on Thursday 1/18/2007 10a Pacific Time (US & Canada) at

This type of change can affect programs in subtle ways. For example, in Outlook 2003/XP/2000, events will be offset an hour during the added weeks of DST unless you apply a patch. Outlook 2007 does not need a patch because the developers were able to anticipate the changes to US time zones. However, users in Mexico need to make sure that they no longer use US/Canadian time zones; there are new time zones for Mexico, because Mexico is not participating in the lengthening of Daylight Savings Time.

Again, it's a subtle issue, so start thinking about how the new law and subsequent changes are going to affect your software and your customers. Microsoft is committed to making this transition as seamless as possible for our users affected by the new DST changes and will be producing an update for Windows products as well as other Microsoft products affected by the law. These updates will be released through multiple technical support and online channels.

Stay tuned for more information!

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