What does UTC stand for?
“Coordinated Universal Time” – Think of this as the true time on Planet Earth that never changes with the exception of minor leap seconds here and there to account for the changes in the planet's rotation.
What does this mean?
Computer time is calculated by taking UTC time, adding an offset that is based on the time zone configured for your computer, and then optionally adjusting the offset for Daylight Saving Time (depending on the DST rules). The formula that is used to calculate computer time is as follows:
UTC + Time zone offset + DST offset
This method represents how people have agreed to think about the concept of time. This method is a world standard, and it is how Microsoft implements time on your computer.
When an appointment, court event or critical date, is sent and the recipients receive the email for the event, it shows the incoming email as:
Note the date and time. In this example it shows Monday, November 3 at 7:00 AM
to Tuesday, November 4 at 7:00 AM UTC.
When the appointment is actually opened up it shows the true date/time of the appointment for the TIME ZONE we are in.
After opening the appointment and closing it, the preview has now changed to the following and no longer shows the UTC time.
Note that this is not “an Outlook problem”, as this is how computers, email clients and mail servers handle time zones.
TZO means Time Zone Offset. This is the time for your geographic region in relation to UTC.
DST means Daylight Savings Time.
WGTZ Database means Windows Global Time Zone Database. This is where windows stores all the time zone and DST rules for the entire planet. It is saved in the Windows registry.
WCTZ Settings means Windows Current Time Zone Settings. This is the settings windows uses to determin the time for your computer.
Computer Time is the time that is displayed by your windows application.
Each of those areas listed above works together in conjunction with UTC.
To calculate the computer time, you take the UTC and add the Time Zone Offset and add the DST offset. This method is the world standard and is how Microsoft calculates the time on your computer.