Information about Time Zones and daylight saving.

A. The following is some useful notes.

User crosses various timezones; uses Control Panel to change the timezone upon arrival.

Windows 95 - System will alter the offset from UTC. System clock is unchanged. Displayed time will NOT be changed.
Windows NT - System will alter the offset from UTC. System clock is unchanged. Displayed date/time WILL change.

Daylight Saving and the "Automatically Adjust for Daylight Saving Time" checkbox

A user arrives the morning of a Daylight Savings Period transition.
If the "Automatically Adjust For Daylight Saving Time" checkbox HAS been enabled

Windows 95 - System will alter the offset from UTC. System clock will be changed. Displayed clock time will change.
Windows NT - System will alter the offset from UTC. System clock is unchanged. Displayed clock time will change.

If the "Automatically Adjust for Daylight Saving Time" checkbox has NOT been enabled

Windows 95 - System WILL alter the offset from UTC. System clock is unchanged. Displayed clock time will NOT be changed.
Windows NT - System will NOT alter the offset from UTC. System clock is unchanged. Displayed clock time will NOT be changed. If an NT user now manually alters the system clock to show the 'true' time, the UTC time is incorrect and any 'export' of time-data from this system will be incorrect.

At some time/day within a Daylight Savings Period, if the user alters the "Automatically Adjust For Daylight Saving Time"

Windows 95 - System will NOT alter the UTC offset. System clock is unchanged. Displayed clock time will NOT be changed.
Windows NT - System WILL alter the UTC offset. System clock is unchanged. Displayed clock time WILL be changed.